The Social Security Administration’s Use of Occupational Information in Disability Determinations: Background and Considerations for Congress

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The Social Security Administration’s Use of

Occupational Information in Disability

Determinations: Background and

Considerations for Congress

December 4, 2025

Congressional Research Service

https://crsreports.congress.gov

R48748

SUMMARY

The Social Security Administration’s Use of

Occupational Information in Disability

Determinations: Background and

Considerations for Congress

R48748

December 4, 2025

Emma K. Tatem

Analyst in Social Policy

For over a decade, as part of its Occupational Information System (OIS) project, the Social

Security Administration (SSA) has been developing a new source of occupational information for making certain disability

determinations under the Social Security Disability Insurance (SSDI) and Supplemental Security Income (SSI) programs.

Despite ongoing congressional interest in the project’s status, to date, SSA has not fully implemented the new OIS.

SSDI and SSI have a work-limiting definition of disability for adults. Under the statutory definition, individuals must have

severe and long-lasting impairments that prevent them from performing substantial gainful activity—defined by SSA as work

resulting in earnings above a set amount. By law, individuals’ impairments must be of such severity as to prevent them from

performing (1) certain work that they have done in the past and (2) any other substantial gainful work that exists in

significant numbers in the national economy, considering their vocational factors of age, education, and work experience.

Sometimes, medical factors alone are enough for SSA to determine that individuals’ impairments meet the disability criteria

in law. In other cases, SSA compares individuals’ remaining work abilities and vocational factors against the requirements of

work in the national economy to make medical-vocational determinations about whether individuals can still perform

substantial gainful work. To do so, SSA requires information about occupations that exist in the U.S. economy, how they are

performed, and their demands, such as the strength and skill levels required to do them. Currently, occupational information

from the Department of Labor’s (DOL’s) Dictionary of Occupational Titles (DOT) forms the basis of SSA’s regulations and

policies for determining the existence of work in the national economy and its requirements, as well as individuals’ abilities

to perform that work.

However, the DOT is widely considered to be outdated. The DOT was last updated in 1991 and as such, DOT occupations

and their associated requirements do not capture labor market changes that have occurred since that time. Furthermore, the

DOT was not designed for SSA disability evaluation and does not contain all the information SSA needs for determining

disability. DOL’s replacement for the DOT, called O*NET, does not meet SSA’s adjudication needs either.

SSA has been partnering with the Bureau of Labor Statistics (BLS) since FY2012 to develop the Occupational Requirements

Survey (ORS). According to SSA, ORS will be the main source of OIS’s updated occupational information along with

selected information from other sources. Between FY2012 and FY2024, SSA obligated over $300 million to the OIS project.

However, SSA has not fully implemented the new OIS. According to SSA, before it can do so, it must first revise its

regulations and internal policies and modify its computer systems.

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SSA’s Use of Occupational Information in Disability Determinations

Contents

Introduction ..................................................................................................................................... 1

Overview of SSA’s Disability Programs ......................................................................................... 1

Social Security Disability Insurance (SSDI) ............................................................................. 1

Supplemental Security Income (SSI) ........................................................................................ 2

Definition of Disability ............................................................................................................. 2

Disability Determination Process .............................................................................................. 2

Step 1. Work Activity Test .................................................................................................. 4

Step 2. Severity and Duration Test ...................................................................................... 4

Step 3. Medical Listings Test .............................................................................................. 4

Residual Functional Capacity (RFC) Assessment .............................................................. 4

Step 4. Previous Work Test ................................................................................................. 5

Step 5. Any Work Test ........................................................................................................ 5

Occupational Information in Initial Adult Disability Determinations ............................................. 6

Dictionary of Occupational Titles (DOT) ................................................................................. 9

Determining Ability to Perform Past Relevant Work ............................................................... 11

Determining Ability to Perform Work That Exists in the National Economy ......................... 12

RFC at Step 5 .................................................................................................................... 12

Vocational Factors ............................................................................................................. 13

The Medical-Vocational Guidelines.................................................................................. 16

Concerns Raised About SSA’s Continued Reliance on the DOT for Disability Evaluation .......... 20

SSA’s Occupational Information System (OIS) Project ................................................................ 22

Occupational Requirements Survey (ORS)............................................................................. 23

Status of OIS ........................................................................................................................... 24

Considerations for Congress.......................................................................................................... 25

Adequacy of Information ........................................................................................................ 25

Project’s Costs ......................................................................................................................... 26

Implementation Timeline ........................................................................................................ 27

Implications of OIS Implementation for SSDI and SSI Eligibility ......................................... 28

Figures

Figure 1. Initial Disability Determination Process for Adult SSDI and SSI Claims ....................... 3

Tables

Table 1. DDS Disability Determinations by Outcome and Reason, 2022 ....................................... 8

Table 2. Limits of Weights Lifted or Carried or of Force Exerted by Exertional Level ................ 13

Table 3. Vocational Factors Considered in SSA Disability Determinations .................................. 15

Table 4. Selected Medical-Vocational Grid Rules Used in SSA Adult Disability

Determinations ........................................................................................................................... 17

Table 5. Applicability of SSA’s Grid Rules in Adult Initial Disability Claims.............................. 19

Table 6. Comparison of Selected DOT and ORS Attributes.......................................................... 24

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SSA’s Use of Occupational Information in Disability Determinations

Contacts

Author Information........................................................................................................................ 28

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SSA’s Use of Occupational Information in Disability Determinations

Introduction

The Social Security Administration (SSA) has been developing a new source of occupational

information for making certain disability determinations under the Social Security Disability

Insurance (SSDI) and Supplemental Security Income (SSI) programs. This effort, known as the

Occupational Information System (OIS) project, has been in progress for over a decade and has

cost over $300 million. Despite ongoing congressional interest in the project’s status, SSA has not

fully implemented OIS. SSA currently relies on occupational information that was last updated in

1991 to decide whether some individuals qualify for benefits under its disability programs.

SSA uses occupational information when it cannot decide disability based solely on medical

factors. In such cases, SSA compares individuals’ remaining work abilities and vocational

factors—age, education, and work experience—against the requirements of work that exists in the

national economy to make medical-vocational determinations about whether individuals can still

perform substantial gainful work.

This report details how SSA currently uses occupational information in disability determinations;

discusses concerns raised by Congress, courts, and others about SSA’s continued reliance on

outdated occupational information in such determinations; describes SSA’s ongoing efforts to

update the occupational information it uses as part of the OIS project; and presents potential

considerations for Congress.

Overview of SSA’s Disability Programs

SSA administers two federal income support programs for people with long-term, work-limiting

disabilities: SSDI and SSI.1 This section provides an overview of the SSDI and SSI programs as

well as the definition of disability and the five-step disability determination process that SSA uses

to evaluate whether adults initially qualify for benefits.

Social Security Disability Insurance (SSDI)

SSDI is part of the Old-Age, Survivors, and Disability Insurance program—commonly known as

Social Security.2 Social Security is a federal social insurance program that provides monthly cash

benefits to insured workers and their eligible family members in the event of the worker’s

retirement, death, or disability. Workers become insured against these events by working for

sufficient periods in jobs that are covered by Social Security and subject to its payroll tax.

The program’s SSDI component provides monthly cash benefits to insured workers below full

retirement age (65-67, depending on year of birth) who experience qualifying disabilities that

limit their ability to work. SSDI benefits are based on insured workers’ career-average earnings in

jobs covered by Social Security. SSDI benefits are primarily financed by dedicated payroll taxes

levied on the earnings of covered workers and credited to the Disability Insurance Trust Fund.

SSDI beneficiaries automatically qualify for health care coverage under Medicare, generally after

serving a 24-month waiting period.

1 For more information on SSDI and SSI, see CRS In Focus IF10506, Social Security Disability Insurance (SSDI); CRS

In Focus IF10482, Supplemental Security Income (SSI); and CRS Report R44948, Social Security Disability Insurance

(SSDI) and Supplemental Security Income (SSI): Eligibility, Benefits, and Financing.

2 For more information on Social Security, see CRS In Focus IF10426, Social Security Overview; and CRS Report

R42035, Social Security Primer.

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Supplemental Security Income (SSI)

SSI is a federal means-tested public assistance program that provides monthly cash benefits to

eligible adults and children who meet the program’s definition of disability and to eligible adults

age 65 or older regardless of their disability status. The program is intended to provide a

guaranteed minimum income to people who have difficulty meeting their basic living expenses

due to disability or age and who have little or no Social Security or other income and limited

resources (i.e., assets). Unlike SSDI, there are no work or contribution requirements to qualify for

SSI. However, because the program is based on need (i.e., means-tested), it is restricted to people

whose countable income and resources are within limits set in law. SSI pays a uniform maximum

monthly benefit, which is reduced by an individual’s countable income (e.g., earnings from work,

Social Security benefits, cash from family or friends). SSI payments are financed by annual

appropriations from the general fund of the U.S. Treasury. Some states supplement the federal

SSI payment using their own funds. In most states, SSI recipients automatically qualify for health

care coverage under Medicaid. SSI is administered by SSA but is separate from Social Security.

Definition of Disability

Both SSDI and SSI use the same long-term, work-limiting definition of disability for adults.3 The

Social Security Act defines disability as the inability to engage in any substantial gainful activity

(SGA) due to any medically determinable physical or mental impairment that is expected to result

in death or has lasted, or is expected to last, for at least 12 consecutive months.4 Under law,

individuals’ impairments must be severe enough to prevent them from performing their past

relevant work (if any) as well as any other substantial gainful work that exists in significant

numbers in the national economy, considering their age, education, and work experience. Such

work need not exist in the immediate area in which an individual lives, nor must a specific job

vacancy exist for the individual.5 SSA generally uses a monthly earnings level specified in

regulations to determine if a person’s work activity represents SGA, which for 2025 is $1,620 per

month for most individuals.6 (SGA amounts are indexed for average wage growth and generally

increase each year.) An individual with monthly earnings over the SGA level is usually

considered able to engage in SGA and would generally be found not disabled for purposes of

SSDI and SSI (although certain exceptions apply). SSDI and SSI do not pay benefits for partial or

short-term disabilities.

Disability Determination Process

SSA uses a five-step sequential evaluation process outlined in its regulations and subregulatory

policies to initially decide whether adults have impairments that meet the disability definition in

law.7 SSA’s initial disability determination process generally proceeds in a set order. At certain

3 Under the SSI program, a different statutory definition of disability applies to individuals under age 18. For more

information, see CRS Report R44948, Social Security Disability Insurance (SSDI) and Supplemental Security Income

(SSI): Eligibility, Benefits, and Financing.

4 Social Security Act, §§223(d)(1)(A) and 1614(a)(3)(A) (42 U.S.C. §§423(d)(1)(A) and 1382c(a)(3)(A)).

5 Social Security Act, §§223(d)(2) and 1614(a)(3)(B) (42 U.S.C. §§423(d)(2) and 1382c(a)(3)(B)).

6 SSA, “Substantial Gainful Activity,” https://www.ssa.gov/oact/cola/sga.html. The SGA earnings level is a proxy

measure for an individual’s ability to perform substantial work for disability evaluation purposes. It is not designed to

be a financial eligibility test.

7 Separate processes are used to periodically re-evaluate whether individuals continue to meet the disability definition

and to determine disability in children. For more information, see CRS Report R44948, Social Security Disability

Insurance (SSDI) and Supplemental Security Income (SSI): Eligibility, Benefits, and Financing.

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steps of this process, SSA may decide that an individual is disabled or not disabled and the initial

determination ends without completing the remaining steps. Individuals may generally be found

disabled for the purpose of disability benefit eligibility at Step 3 of the process based on medical

factors or at Step 5 of the process based on medical and vocational factors. Individuals may

generally be found not disabled at any step except Step 3 (Figure 1).8

Figure 1. Initial Disability Determination Process for Adult SSDI and SSI Claims

Source: CRS based on Subpart P of 20 C.F.R. §404 and Subpart I of 20 C.F.R. §416.

8 20 C.F.R. §§404.1520 and 416.920.

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SSA’s Use of Occupational Information in Disability Determinations

Step 1. Work Activity Test

At Step 1 of the disability determination process, SSA assesses whether individuals are working

and earning above the SGA earnings level (i.e., $1,620 per month for most individuals in 2025).9

Individuals who are working above the SGA earnings level are found not disabled. Individuals

who are working at or below the SGA earnings level proceed to Step 2.

Step 2. Severity and Duration Test

At Step 2, federally funded state Disability Determination Services (DDS) agencies—which make

disability determinations on behalf of SSA—determine whether individuals have impairments of

sufficient severity and duration.10 An individual must have a severe medically determinable

physical or mental impairment that is expected to result in death or has lasted or is expected to

last for at least one full year.11 SSA considers a severe impairment to be one that significantly

limits an individual’s physical or mental ability to do basic work activities.12 Individuals who do

not have impairments that meet the severity and duration criteria are found not disabled.

Individuals who have impairments that meet the severity and duration criteria proceed to Step 3.

Step 3. Medical Listings Test

At Step 3, the DDS will compare an individual’s impairment(s) against the medical and

functional criteria of impairments included in SSA’s regulatory Listing of Impairments

(commonly referred to as “the listings”).13 The listings for adults contain examples of medically

determinable impairments that SSA considers severe enough to prevent individuals from

performing any gainful activity, regardless of their age, education, or work experience—in other

words, those impairments that SSA has determined meet the definition of disability in law based

on medical factors alone. The listings were created to quickly screen relatively clear-cut cases,

leaving SSA more time to evaluate more difficult cases at the latter stages of the process.

Individuals with impairments that meet or medically equal the criteria of listed impairments are

found disabled. Individuals with impairments that do not meet or equal the criteria of listed

impairments proceed to Step 4 after SSA first determines their residual functional capacity (RFC).

Residual Functional Capacity (RFC) Assessment

If medical factors alone are not enough to find that an individual meets the definition of disability

at Step 3, the DDS will generally perform a function-by-function assessment to determine the

individual’s RFC. An individual’s RFC is typically his or her maximum remaining ability to do

sustained work activities in an ordinary work setting on a regular and continuing basis (i.e., eight

hours a day, for five days a week, or an equivalent work schedule).14 In other words, it is the most

that the individual can do despite the limitations or restrictions caused by his or her medically

9 SSA, “Substantial Gainful Activity.”

10 For more information on DDSs, see Social Security Advisory Board, “Social Security and State Disability

Determination Services Agencies: A Partnership in Need of Attention,” April 6, 2023, https://www.ssab.gov/research/

social-security-and-state-dds-agencies-partnership-in-need-of-attention/.

11 20 C.F.R §§404.1509, 404.1521, 416.909, and 416.921.

12 20 C.F.R. §§404.1522 and 416.922.

13 20 C.F.R. §§404.1525 and 416.925; Appendix 1 to Subpart P of Part 404, 20 C.F.R.

14 SSA, “SSR 96-8p: Policy Interpretation Ruling Titles II and XVI: Assessing Residual Functional Capacity in Initial

Claims,” July 2, 1996, https://www.ssa.gov/OP_Home/rulings/di/01/SSR96-08-di-01.html.

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determinable impairment(s).15 The RFC assessment considers both the individual’s remaining

exertional and nonexertional capacities for performing sustained, work-related activities. An

individual’s exertional capacity is his or her maximum remaining ability to do each of seven

physical-strength-related activities: sitting, standing, walking, lifting, carrying, pushing, and

pulling.16 An individual’s nonexertional capacity is his or her maximum remaining ability to do

activities not related to physical strength, including stooping, climbing, reaching, handling,

seeing, hearing, speaking, understanding and remembering instructions, responding appropriately

to supervision, and tolerating temperature extremes.17 Individuals may have only exertional or

nonexertional limitations or restrictions, or they may have a combination of both.18 The RFC

includes a narrative discussion of the individual’s ability to do the above work-related activities

and the maximum amount of the activities that the individual can perform based on the evidence

in the case record.19 The DDS uses the RFC assessment in disability determinations involving

both medical and vocational factors, which are made at Steps 4 and 5.20 For example, at Step 5,

the DDS may determine that the individual’s RFC limits him or her to performing, at most,

sedentary work.

Step 4. Previous Work Test

At Step 4, DDSs will determine whether individuals, given their RFCs, can perform their past

relevant work (if any) as they actually performed it or as it is generally performed in the national

economy.21 SSA’s regulations define past relevant work as work that an individual did within the

past five years that (1) was SGA, (2) lasted long enough for the individual to learn to do it, and

(3) was performed for at least 30 consecutive days.22 Individuals who can do their past relevant

work are found not disabled. Individuals who cannot do their past relevant work (or do not have

any past relevant work) proceed to Step 5.

Step 5. Any Work Test

At Step 5, DDSs will decide whether individuals who cannot do their past relevant work (or do

not have any past relevant work) can adjust to any other substantial gainful work that exists in

significant numbers in the national economy given their RFCs and considering the vocational

factors of their age, education, and work experience.23 It does not matter whether the work exists

in the immediate area where the individuals live, whether specific job vacancies exist for them, or

15 20 C.F.R. §§404.1545 and 416.945; SSA, Program Operations Manual System (POMS), “DI 24510.006 Assessing

Residual Functional Capacity (RFC) in Initial Claims (SSR 96-8p),” February 12, 2025, https://secure.ssa.gov/

poms.nsf/lnx/0424510006.

16 SSA, POMS, “DI 24510.006 Assessing Residual Functional Capacity (RFC) in Initial Claims (SSR 96-8p),”

February 12, 2025, https://secure.ssa.gov/poms.nsf/lnx/0424510006.

17 SSA, POMS, “DI 24510.006 Assessing Residual Functional Capacity (RFC) in Initial Claims (SSR 96-8p).”

18 SSA, POMS, “DI 24510.006 Assessing Residual Functional Capacity (RFC) in Initial Claims (SSR 96-8p).”

19 SSA, “SSR 96-8p: Policy Interpretation Ruling Titles II and XVI.”

20 20 C.F.R. §§404.1545 and 416.945.

21 20 C.F.R. §§404.1560 and 416.960.

22 20 C.F.R. §§404.1560 and 416.960. SSA used to consider past relevant work to be work that an individual did above

the SGA earnings level within the past 15 years before the individual’s disability onset, until a rule change, which took

effect on June 22, 2024, shortened the lookback period to five years and added the 30-day minimum requirement. See

SSA, “Intermediate Improvement to the Disability Adjudication Process, Including How We Consider Past Work,” 89

Federal Register 27653, April 18, 2024, https://www.federalregister.gov/d/2024-08150; and SSA, “Intermediate

Improvement to the Disability Adjudication Process, Including How We Consider Past Work,” 89 Federal Register

48138, June 5, 2024, https://www.federalregister.gov/d/2024-12285.

23 20 C.F.R. §§404.1560 and 416.960.

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whether they would be hired for such work.24 Unlike at Steps 1-4, at Step 5 the DDS bears the

responsibility of providing evidence that there is work that exists in significant numbers in the

national economy that individuals can perform.25 Individuals determined able to adjust to other

work by the DDS are found not disabled. Individuals determined unable to adjust to other work

are found disabled.

Step 5 completes the disability determination process, at which point the DDS relays the

determination to SSA to finalize processing and issue the initial disability benefit award or denial

notice.

In 2022, about 1.6 million people applied for SSDI worker benefits.26 Of those who applied and

received disability determinations, 34.6% were allowed by DDSs at the initial level.27 In 2022,

roughly 0.8 million adults ages 18-64 applied for SSI payments.28 Of those adults who applied

and received disability determinations, 31.3% were allowed by DDSs at the initial level.29

Individuals who receive initial favorable disability determinations from the DDSs may later be

denied by SSA for technical reasons. An individual who disagrees with SSA’s initial

determination may appeal the decision under certain conditions.30

Occupational Information in Initial Adult Disability

Determinations

To meet the definition of disability under SSDI and SSI, the law requires adults to have medically

determinable impairments of sufficient duration that is severe enough to prevent them from

performing both (1) their past relevant work and (2) any other substantial gainful work that exists

in significant numbers in the national economy, considering the vocational factors of their age,

24

20 C.F.R. §§404.1566 and 416.966.

25 20 C.F.R. §§404.1512(b)(3), 404.1560(c)(2), 416.912(b)(3), and 416.960(c)(2); SSA, POMS, “HA 02530.003

Express Written Acknowledgement of the Limited Shifting of the Burden at the Last Step of the Sequential Evaluation

Process,” December 14, 2005, https://secure.ssa.gov/apps10/poms.nsf/lnx/2502530003; and SSA, Office of Hearings

Operations, Office of the Chief Administrative Law Judge, Vocational Expert Handbook, January 6, 2025, p. 26,

https://www.ssa.gov/appeals/public_experts/Vocational_Experts_(VE)_Handbook-508_Jan25.pdf.

26 SSA, “Annual Statistical Report on the Social Security Disability Insurance Program, 2023,” Table 60,

https://www.ssa.gov/policy/docs/statcomps/di_asr/2023/sect04.html. SSDI worker data include Social Security–only

and concurrent Social Security and SSI claims.

27 SSA, “Annual Statistical Report on the Social Security Disability Insurance Program, 2023,” Table 61. SSDI worker

data include Social Security–only and concurrent Social Security and SSI claims with medical decisions at the initial

level of review. They exclude cases that were denied for technical reasons before reaching the DDSs. SSA data are

subject to revision and may change over time.

28 SSA, “SSI Annual Statistical Report, 2023,” Table 69, https://www.ssa.gov/policy/docs/statcomps/ssi_asr/2023/

sect10.html. SSI adult data include SSI-only and concurrent Social Security and SSI claims.

29 SSA, “SSI Annual Statistical Report, 2023,” Table 70. SSI adult data include SSI-only and concurrent Social

Security and SSI claims with medical decisions at the initial level of review. They exclude cases that were denied for

technical reasons before reaching the DDSs. SSA data are subject to revision and may change over time.

30 Social Security Act, §§205(b)(1) and 1631(c)(1)(A); 42 U.S.C. §§405(b)(1) and 1383(c)(1)(A). SSA’s administrative

appeals process generally consists of three levels of review: (1) a second complete review—called a reconsideration—

of the individual’s claim by a new reviewer who was not involved in the initial determination (reconsiderations of

disability determinations are performed by state DDSs), (2) a hearing before an administrative law judge, and (3) a

review of the case by the SSA Appeals Council. An individual usually must exhaust all three levels of SSA

administrative review sequentially and receive a final decision from SSA before filing a civil action in a federal district

court. Appeals of unfavorable disability determinations may involve an individual’s ability to perform his or her past

work or adjust to other work that exists in the national economy where SSA considers occupational information.

However, this report focuses on SSA’s use of occupational information at the initial level.

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education, and work experience.31 Under SSA’s five-step disability determination process, SSA

sometimes determines that an individual meets the statutory definition of disability based on

medical factors alone. SSA makes this type of allowance when, based on its own medical criteria,

it determines that the individual’s impairment is so severe that it would prevent anyone—

regardless of age, education, or work experience—from performing any gainful work (i.e., Step

3).

However, this is a stricter definition of disability than the definition provided in law, which

requires SSA to consider the combined effect of the individual’s impairment and vocational

factors (i.e., age, education, and work experience) on his or her ability to perform substantial

gainful work that exists in the national economy.32 To make these latter types of disability

determinations involving medical and vocational factors, SSA uses occupational information—

mainly from the Dictionary of Occupational Titles (DOT)—along with individuals’ RFCs—to

determine whether they can perform their past relevant work (i.e., Step 4) or adjust to any other

work that exists in significant numbers in the national economy given their vocational factors

(i.e., Step 5).33

As shown in Table 1, in 2022, 47.0% of the favorable disability determinations (i.e., allowances)

made by DDSs on SSDI worker cases involved the consideration of an individual’s ability to

perform other work (i.e., medical factors alone were not enough to find the individual disabled),

and 40.1% of favorable disability determinations made by DDSs on adult SSI cases involved the

consideration of an individual’s ability to perform other work.34

Of all of the unfavorable disability determinations (i.e., denials) made by DDSs on SSDI worker

cases in 2022, 7.6% were denied based on determinations that the individuals could do their past

work, and 35.8% were denied based on determinations that the individuals were able to adjust to

other work that exists in significant numbers in the national economy.35 Of all the unfavorable

disability determinations on adult SSI cases made by DDSs in 2022, 3.3% were denied based on

determinations that individuals could do their past work, and 44.2% were denied based on

determinations that the individuals were able to adjust to other work that exists in significant

numbers in the national economy (Table 1).36

31 Social Security Act, §§223(d) and 1614(a)(3) (42 U.S.C. §§423(d) and 1382c(a)(3)).

32 Social Security Act, §§223(d)(2)(A) and 1614(a)(3)(B) (42 U.S.C. §§423(d)(2)(A) and 1382c(a)(3)(B)).

33 20 C.F.R. §§404.1560 and 416.960. For more information see SSA, Occupational Information Development

Advisory Panel (OIDAP), Report of the Mental Cognitive Subcommittee of the Occupational Information Development

Advisory Panel, September 1, 2009, pp. C-74-79, https://web.archive.org/web/20250124021602/https://www.ssa.gov/

oidap/Documents/AppendixC.pdf.

34 SSA, “Annual Statistical Report on the Social Security Disability Insurance Program, 2023,” Table 64; and SSA,

“SSI Annual Statistical Report, 2023,” Table 73. SSDI data include Social Security–only and concurrent Social

Security and SSI claims with medical decisions at all levels of review and do not include SSI-only cases. SSI data

include SSI-only and concurrent Social Security and SSI claims with medical decisions at all levels of review and do

not include Social Security–only cases. Cases allowed for medical reasons (i.e., medically allowed) may later be denied

for nonmedical reasons. Data are subject to revision and may change over time.

35 SSA, “Annual Statistical Report on the Social Security Disability Insurance Program, 2023,” Table 65. The ability to

do other work was the most common reason for medical denial in 2022. These data include Social Security–only and

concurrent Social Security and SSI claims with medical decisions at all levels of review and do not include SSI-only

cases. Data are subject to revision and may change over time.

36 These data include SSI-only and concurrent Social Security and SSI claims with medical decisions at all levels of

review and do not include Social Security–only cases. SSA, “SSI Annual Statistical Report, 2023,” Table 74.

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Table 1. DDS Disability Determinations by Outcome and Reason, 2022

Allowed by the DDS

Denied by the DDS

Total

At Step 2

Based on

Medical

Factors

At Step 4

Based on

Ability to

Do Past

Relevant

Work

At Step 5

Based on

Ability to

Do Any

Other

Work

For Other

Reasonsb

Total

2.7%

100.0%

21.9%

7.6%

35.8%

34.8%

100.0%

4.2%

100.0%

6.9%

3.3%

44.2%

45.5%

100.0%

Program

At Step 3

Based on

Medical

Factors

Alone

At Step 5 Based

on MedicalVocational

Factors

For Other

Reasonsa

SSDI

50.2%

47.0%

SSI

55.7%

40.1%

Source: SSA, “Annual Statistical Report on the Social Security Disability Insurance Program, 2023,” Tables 64 and 65, https://www.ssa.gov/policy/docs/statcomps/di_asr/

2023/sect04.html; and SSA, “SSI Annual Statistical Report, 2023,” Tables 73 and 74, https://www.ssa.gov/policy/docs/statcomps/ssi_asr/2023/sect10.html.

Notes: SSDI = Social Security Disability Insurance; SSI = Supplemental Security Income. Data are for applications submitted in 2022. SSDI data represent workers only

and include Social Security–only and concurrent Social Security and SSI claims with medical decisions at all levels of review. SSI data represent adults only and include SSIonly and concurrent Social Security and SSI claims with medical decisions at all levels of review. Medically allowed cases may later be denied for nonmedical reasons. SSA

data are subject to revision and may change over time. Percentages may not sum to 100.0 due to rounding.

a. Other factors may include cases in which disability was previously established and in which the basis for the determination is not available.

b. Other factors for SSDI may include cases in which the applicant has an impairment resulting from drug addiction or alcoholism, provided insufficient medical

evidence, failed to cooperate, failed to follow prescribed treatment, did not want to continue development of the claim, and returned to substantial work before

disability could be established and cases denied at or above the hearing level for which the basis of determination is not available. Other factors for SSI may include

cases in which the applicant provided insufficient evidence, failed to cooperate, failed to follow prescribed treatment, did not want to continue development of the

claim, or returned to substantial work before disability could be established.

CRS-8

SSA’s Use of Occupational Information in Disability Determinations

To make determinations about whether individuals can do their past work or adjust to other work,

SSA needs information about occupations in the national economy, including what occupations

exist, how they are performed, and the requirements needed to perform them (e.g., strength and

training levels). SSA’s regulations currently consider “reliable job information” for determining

the existence and requirements of work to include information from the Department of Labor’s

(DOL’s) DOT, the Census Bureau’s County Business Patterns and other Census reports, the

Bureau of Labor Statistics’ (BLS’) Occupational Outlook Handbook, and other occupational

analyses prepared for SSA by state employment agencies.37 According to its regulations, SSA

may also use evidence provided by vocational specialists or vocational experts when assessing an

individual’s ability to perform past or other work.38

Dictionary of Occupational Titles (DOT)

While SSA’s regulations specify several sources of “reliable job information” that SSA may use,

its primary source of occupational information is currently the DOT.39 The DOT is a publication

developed by DOL in 1938 and last updated in 1991 that contains information about over 12,000

U.S. occupations and their requirements. DOL field analysts prepared occupational information in

the DOT based on their observations from visiting a selection of “typical” business

establishments within particular industries.40

The DOT defines occupation as a “collective description of a number of individual jobs

performed, with minor variations, in many establishments.”41 An occupational definition in the

DOT generally includes a unique code identifying the occupation (i.e., DOT code); an

occupational title (i.e., DOT title); an industry designation; a description of the occupation and

how it is performed; and other selected characteristics of the occupation, such as the occupation’s

exertional (i.e., physical strength) level (i.e., sedentary, light, medium, heavy, or very heavy) and

its Specific Vocational Preparation (SVP) level, which measures how long it takes a typical

worker to develop the skills needed for average performance in the occupation.42 For example,

the entry for the DOT title of administrative clerk (DOT Code 219.362-010) reads:

219.362-010 ADMINISTRATIVE CLERK (clerical) alternate titles: clerk, general office

Compiles and maintains records of business transactions and office activities of

establishment, performing variety of following or similar clerical duties and utilizing

knowledge of systems or procedures: Copies data and compiles records and reports.

37 20 C.F.R. §§404.1566 and 416.966.

38 20 C.F.R. §§404.1566 and 416.966. According to SSA’s policies, disability examiners (DEs) at state DDSs are able

to evaluate most vocational issues. However, DEs may also seek the expertise of vocational specialists (VSs) in cases

involving complex vocational issues that are beyond the DEs’ levels of expertise. See SSA, POMS, “DI 25003.001

Vocational Specialists,” February 6, 2025, https://secure.ssa.gov/poms.nsf/lnx/0425003001. In certain circumstances,

DDSs are directed to obtain evidence from VSs. VSs are individuals designated by DDSs (e.g., senior DEs) who have

specialized knowledge of and experience with vocational issues—including as they apply to Steps 4 and 5 of SSA’s

disability determination process—and have completed SSA-sponsored training. See SSA, POMS, “DI 25003.001

Vocational Specialists”; and SSA, POMS, “DI 25003.005 Designating Vocational Specialists,” July 3, 2024,

https://secure.ssa.gov/apps10/poms.nsf/lnx/0425003005.

39 20 C.F.R. §§404.1566 and 416.966; SSA, “Occupational Information System Project FAQ’s,” https://www.ssa.gov/

disabilityresearch/ois_project_faqs.html.

40 Michael J. Handel, Methodological Issues Related to the Occupational Requirements Survey, February 26, 2015, p.

10, https://www.bls.gov/ors/research/collection/pdf/handel-methodological-issues-data-collection-full-report-feb15.pdf.

41 DOL, Dictionary of Occupational Titles (4th Ed., Rev. 1991)—Parts, available at https://www.dol.gov/agencies/oalj/

PUBLIC/DOT/REFERENCES/DOTPARTS.

42 DOL, Dictionary of Occupational Titles (4th Ed., Rev. 1991)—Appendix C, available at https://www.dol.gov/

agencies/oalj/PUBLIC/DOT/REFERENCES/DOTAPPC.

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Tabulates and posts data in record books. Computes wages, taxes, premiums, commissions,

and payments. Records orders for merchandise or service. Gives information to and

interviews customers, claimants, employees, and sales personnel. Receives, counts, and

pays out cash. Prepares, issues, and sends out receipts, bills, policies, invoices, statements,

and checks. Prepares stock inventory. Adjusts complaints. Operates office machines, such

as typewriter, adding, calculating, and duplicating machines. Opens and routes incoming

mail, answers correspondence, and prepares outgoing mail. May take dictation. May greet

and assist visitors. May prepare payroll. May keep books. May purchase supplies. May

operate computer terminal to input and retrieve data. May be designated according to field

of activity or according to location of employment as Adjustment Clerk (retail trade; tel. &

tel.); Airport Clerk (air trans.); Colliery Clerk (mine & quarry); Death-Claim Clerk

(insurance); Field Clerk (clerical). May be designated: Agency Clerk (insurance); Auction

Clerk (clerical); Construction-Records Clerk (construction; utilities); Shop Clerk (clerical).

GOE: 07.01.02 STRENGTH: L GED: R4 M3 L3 SVP: 4 DLU: 88.43

In 1966, DOL partnered with SSA to publish a companion to the DOT, the Selected

Characteristics of Occupations (SCO), which provides additional information about selected

physical and environmental demands of DOT occupations for SSA’s purposes.44 Like the DOT,

the SCO was last updated in the early 1990s.45

Court decisions and a change to the statutory definition of disability in the 1960s required SSA to

begin considering the existence of work in the national economy when disability determinations

could not be made based on medical factors alone.46 SSA found that, of the occupational sources

that existed at that time, the DOT was best able to meet its legal and programmatic requirements

for making such determinations.47 Consequently, SSA’s regulations and policies for assessing

whether individuals remain capable of performing the requirements of their past work or of any

43 DOL, Dictionary of Occupational Titles (4th Ed., Rev. 1991)—Clerical and Sales Occupations 201.162-010 to

219.362-046, available at https://www.dol.gov/agencies/oalj/PUBLIC/DOT/REFERENCES/DOT02A. The last line of

the occupational definition is referred to as the definition trailer, which lists selected characteristics of the occupation.

GOE refers to Guide for Occupational Exploration. The GOE code is made up of three pairs of numbers, which classify

the occupation according to interest area (first pair of digits), work group (second pair of digits), and subgroup (last pair

of digits). Strength refers to the occupation’s strength rating, which is expressed as one of five letters that correspond to

the five possible strength ratings: S for sedentary, L for light, M for medium, H for heavy, or V for very heavy. GED

refers to General Education Development. The GED scale consists of three pairs of letters and numbers corresponding

to the occupation’s level of reasoning development (R), mathematical development (M), and language development

(L), respectively. SVP refers to Specific Vocational Preparation, which is expressed as a number on a scale from one to

nine that measures the amount of time needed for the typical worker to develop the skills needed for average

performance in the occupation. Occupations with an SVP of one require only a short demonstration and occupations

with an SVP of nine require over 10 years. DLU refers to the Date of Last Update, which is the last two digits of the

last year in which information was gathered about the occupation. The DOT was last updated in 1991, so the latest

possible DLU is “91.”

44

DOL, Selected Characteristics of Occupations (Physical Demands, Working Conditions, Training Time): A

Supplement to the Dictionary of Occupational Titles, Third Edition, 1966, available at https://books.google.com/books?

id=umKElbjjwdEC&pg=PR1#v=onepage&q&f=false.

45 DOL, Selected Characteristics of Occupations Defined in the Revised Dictionary of Occupational Titles, 1993,

available at https://babel.hathitrust.org/cgi/pt?id=umn.31951d00286799y&view=1up&seq=1; and SSA, Occupational

Information System Fiscal Year 2011 Research and Development Plan, July 2011, p. 60, https://web.archive.org/web/

20250222155838/https://www.ssa.gov/oidap/Documents/FINAL%20POSTED%20VERSION—

2011%2007%2025%20OIS%20RD%20Plan.pdf. Hereinafter, the term DOT generally refers to both the DOT and the

companion SCO.

46 SSA, Occupational Information System Fiscal Year 2011 Research and Development Plan, pp. 59-60.

47 SSA, Occupational Information System Fiscal Year 2011 Research and Development Plan, p. 60.

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other work that exists in significant numbers in the national economy came to be based on DOT

concepts.48

Determining Ability to Perform Past Relevant Work

In cases that cannot be decided based on medical factors alone (i.e., those reaching Step 4 of the

disability determination process), DDSs (on behalf of SSA) generally first consider whether

individuals can still perform their past relevant work (if any). Past relevant work is work that (1)

an individual performed within the past five years; (2) was SGA; (3) lasted long enough for the

individual to learn to do it49; and (4) was not started and stopped in fewer than 30 consecutive

days.50

Under SSA’s regulations, DDSs will find that individuals are not disabled if they can still do any

of their past relevant work as they actually performed it or as it is generally performed in the

national economy.51 To do so, the DDS typically compares, on a function-by-function basis, the

individual’s RFC with the exertional and non-exertional demands of the individual’s past relevant

work.

According to SSA, when assessing whether individuals can still do their past relevant work as

they actually performed it, DDSs primarily consider information supplied by the individuals

about that work, such as the duties they performed; the tools, machinery, or equipment they used;

and details about the physical, mental, and other requirements of the work they did.52 In some

cases, the DDS may contact the individual’s past employer or another source for additional

information.53

SSA’s guidance directs a DDS, when determining how an individual’s past relevant work is

generally performed in the national economy, to use the DOT, or another reliable source of

occupational information, to locate the occupational counterpart for each of the individual’s past

relevant jobs and identify the functional demands of those occupations.54 Per SSA, the DDS may

also seek information from a vocational specialist or expert about how a particular occupation is

usually performed in the national economy.55

Under SSA’s rules, if the demands of an individual’s past relevant work—as actually or generally

performed—are within the individual’s RFC, the DDS should determine that the individual can

still perform that work and, thus, is not disabled.56 Per SSA’s regulations, the DDS determines

whether an individual can perform his or her past relevant work without regard to the individual’s

48 OIDAP, Content Model and Classification Recommendations for the Social Security Administration Occupational

Information System, September 2009, p. 8, https://web.archive.org/web/20250222071422/https://www.ssa.gov/oidap/

Documents/FinalReportRecommendations.pdf.

49 Long enough to learn to do it means that the individual performed the job long enough to “learn the techniques,

acquire information, and develop the facility needed for average performance in the job,” which “depends on the nature

and complexity of the work” and “may be expressed as specific vocational preparation (SVP).” SSA, “SSR 24-2p:

Titles II and XVI: How We Evaluate Past Relevant Work,” June 22, 2024, https://www.ssa.gov/OP_Home/rulings/di/

02/SSR2024-02-di-02.html.

50 20 C.F.R. §§404.1560(b), 404.1565(a), 416.960(b), and 416.965(a); SSA, “SSR 24-2p: Titles II and XVI.”

51 20 C.F.R. §§404.1560(b) and 416.960(b).

52 SSA, “SSR 24-2p: Titles II and XVI.”

53 SSA, “SSR 24-2p: Titles II and XVI.”

54 SSA, POMS, “DI 25005.025 Past Relevant Work (PRW) as Generally Performed in the National Economy,” January

3, 2025; SSA, “SSR 24-2p: Titles II and XVI.”

55 SSA, “SSR 24-2p: Titles II and XVI.”

56 20 C.F.R. §§404.1560(b) and 416.960(b).

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vocational factors (i.e., his or her age, education, or work experience) or whether the work exists

in significant numbers in the national economy.57 If an individual is found unable to perform any

of his or her past relevant work as actually or generally performed, the DDS then considers

whether the individual can do any other work that exists in significant numbers in the national

economy, considering his or her age, education, and work experience (i.e., Step 5).58

Determining Ability to Perform Work That Exists in the National

Economy

In cases where individuals cannot do their past relevant work (i.e., those reaching Step 5 of the

disability determination process), DDSs next determine whether individuals are able to perform

any other work that exists in significant numbers in the national economy. To do so, the DDS will

consider the individual’s RFC—his or her maximum remaining ability to do sustained work

activities in an ordinary work setting on a full-time basis—and vocational factors—age,

education, and work experience. If the DDS can show, using its medical-vocational guidelines,

that an individual’s combination of RFC and vocational factors allows him or her to adjust to

other work that exists in the national economy, the DDS will determine that the individual is not

disabled.59

RFC at Step 5

An individual’s RFC is a function-by-function assessment of both his or her exertional (i.e.,

strength-related) and nonexertional (i.e., other than strength-related) work capabilities.60 At Step 5

of the disability determination process, an individual’s RFC is generally expressed in terms of an

exertional work category (i.e., his or her maximum remaining ability to do sedentary, light,

medium, heavy, or very heavy work).61 Per its regulations, SSA’s definitions of sedentary, light,

medium, heavy, and very heavy are based on those in the DOT.62 Table 2 is reproduced from

SSA’s policy manual and shows the general lifting and carrying requirements of work at each

exertional level as specified in SSA’s policies and the DOT.63 According to SSA’s policies, for the

DDS to determine that an individual can do the full range of work at a given exertional level, the

individual must be able to perform “substantially all” of both the exertional and the nonexertional

(e.g., mental, environmental) work functions required in jobs at that level considering the

limitations and restrictions caused by his or her impairment.64 Individuals determined capable of

performing the exertional requirements of work at a given level are also presumed able to

57 20 C.F.R. §§404.1560(b) and 416.960(b).

58 20 C.F.R. §§404.1560(c) and 416.960(c). In certain cases, SSA will determine whether individuals are able to adjust

to other work under an expedited process that does not consider their ability to perform their past relevant work. See 20

C.F.R. §§404.1520(h) and 416.920(h).

59 20 C.F.R. §§404.1560(c) and 416.960(c).

60 SSA, “SSR 96-8p: Policy Interpretation Ruling Titles II and XVI.”

61 Appendix 2 to Subpart P of Part 404, 20 C.F.R., and SSA, “SSR 96-8p: Policy Interpretation Ruling Titles II and

XVI.”

62 20 C.F.R. §§404.1567, 404.1569a, 416.967, and 416.969a; SSA, POMS, “DI 25001.001 Medical and Vocational

Quick Reference Guide,” January 3, 2025, https://secure.ssa.gov/poms.nsf/lnx/0425001001.

63 SSA, POMS, “DI 25001.001 Medical and Vocational Quick Reference Guide.”

64 SSA, “SSR 96-8p: Policy Interpretation Ruling Titles II and XVI.”

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perform the exertional requirements of work at any lower levels.65 For example, an individual

determined able to do medium work is also assumed able to do light work and sedentary work.66

Table 2. Limits of Weights Lifted or Carried or of Force Exerted by Exertional Level

In Pounds

Exertional Level

Occasionally

Frequently

Constantly

Sedentary

* to 10

*

N/A

Light

* to 20

* to 10

*

Medium

20 to 50

10 to 25

* to 10

Heavy

50 to 100

25 to 50

10 to 20

100 and over

50 and over

20 and over

Very Heavy

Source: CRS reproduced from SSA, POMS, “DI 25001.001 Medical and Vocational Quick Reference Guide,”

January 3, 2025, https://secure.ssa.gov/poms.nsf/lnx/0425001001. Also see 20 C.F.R. §§404.1567 and 416.967 and

DOL, Dictionary of Occupational Titles (4th Ed., Rev. 1991)—Appendix C, available at https://www.dol.gov/agencies/

oalj/PUBLIC/DOT/REFERENCES/DOTAPPC.

Notes: * = negligible weight; N/A = not applicable.

Vocational Factors

In combination with an individual’s RFC, SSA considers the individual’s vocational factors of

age, education, and work experience when determining whether he or she can adjust to other

work that exists in the national economy.

Age is an individual’s chronological age. In general, SSA considers that as individuals age, they

are increasingly limited in their ability to adjust to other work. SSA’s regulations specify three age

categories67:

1. Younger person. A younger person is under age 50. According to SSA, age

generally does not influence a younger person’s ability to adjust to other work.68

2. Person closely approaching advanced age. A person closely approaching

advanced age is age 50-54. At these ages, SSA considers whether the individual’s

age, in combination with other factors, may significantly affect his or her ability

to adjust to other work.

3. Person of advanced age. A person of advanced age is age 55 or older. Under

SSA’s regulations, being of advanced age significantly limits an individual’s

ability to adjust to other work.

65 Appendix 2 to Subpart P of Part 404, 20 C.F.R.

66 SSA, “SSR 96-8p: Policy Interpretation Ruling Titles II and XVI.”

67 20 C.F.R. §§404.1563 and 416.963 and SSA, POMS, “DI 25015.005 Age as a Vocational Factor,” December 14,

2023, https://secure.ssa.gov/apps10/poms.nsf/lnx/0425015005.

68 Exceptions apply for individuals ages 45-49. See SSA, POMS, “DI 25015.005 Age as a Vocational Factor.”

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Education is “formal schooling or other training which contributes to [an individual’s] ability to

meet vocational requirements” of work.69 SSA’s regulations and policies specify four primary

education categories70:

1. Illiteracy. SSA generally considers individuals to be illiterate if they cannot read

or write a simple message in any language.

2. Marginal education. SSA considers individuals to have marginal education if

they have completed formal schooling in any country at a sixth-grade level or

below.

3. Limited education. SSA considers individuals to have limited education if they

have completed formal schooling in any country at a seventh- through eleventhgrade level.

4. High school education or above. SSA considers individuals to have high school

education or above if they have completed formal schooling in any country at a

twelfth-grade level or above. SSA may also consider whether certain older

individuals with a high school education or above have recently completed

education that provides for direct entry into skilled or semiskilled work.

Work experience is the skills and abilities that individuals have gained from their past relevant

work that indicate the type of work that they may be expected to adjust to.71 The skill level of

work is related to the SVP measures found in the DOT.72 SVP is a numeric scale corresponding to

how long it takes a typical worker to develop the skills needed for average performance in an

occupation. Occupations with an SVP of one require a “short demonstration only,” while those

with an SVP of nine require “over 10 years.”73 For example, the previously discussed DOT title

of administrative clerk had an SVP of 4, meaning it would require “over 3 months up to and

including 6 months” for a typical worker to attain average performance in that occupation. SSA’s

policies specify four categories of work experience74:

1. No work experience. SSA considers individuals to have no work experience if

they have no past relevant work experience.

2. Unskilled work experience. Under SSA’s regulations and policies, unskilled work

experience consists of simple duties that require little to no judgment and can be

learned on the job in 30 days or less (i.e., work with an SVP of one or two).

3. Semiskilled or skilled work experience with no transferable skills. Semiskilled

work experience requires some skills, does not require complex duties, and takes

one to six months to learn (i.e., work with an SVP of three or four). Skilled work

experience consists of skilled job functions, requires “good” cognitive

functioning, and takes over six months to learn (i.e., work with an SVP of five to

nine). SSA may also evaluate whether individuals with semiskilled or skilled

work experience have acquired transferable skills that they can apply in other

69 20 C.F.R. §§404.1564 and 416.964.

70 20 C.F.R. §§404.1564 and 416.964 and SSA, POMS, “DI 25015.010 Education as a Vocational Factor,” August 6,

2020, https://secure.ssa.gov/poms.nsf/lnx/0425015010.

71 20 C.F.R. §§404.1565 and 416.965.

72 SSA, POMS, “DI 25015.015 Work Experience as a Vocational Factor,” July 5, 2024, https://secure.ssa.gov/

poms.nsf/lnx/0425015015.

73 DOL, Dictionary of Occupational Titles, Appendix C.

74 20 C.F.R. §§404.1568 and 416.968; SSA, POMS, “DI 25015.015 Work Experience as a Vocational Factor”; SSA,

POMS, “DI 25001.001 Medical and Vocational Quick Reference Guide.”

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work. Transferable skills are skills resulting from skilled or semiskilled work

experience that can be applied in other work that is within an individual’s RFC.75

4. Semiskilled or skilled work experience with transferable skills.

Table 3 summarizes the vocational factors that are considered in SSA’s disability determination

process.

Table 3. Vocational Factors Considered in SSA Disability Determinations

Factor

Age

Educationc

Work Experienced

Categories

Description

Advanced agea

Age 55 or older

Closely approaching advanced age

Ages 50-54

Youngerb

Under age 50

Illiteracy

Cannot read or write a simple message

Marginal

6th grade level or below

Limited

7th-11th grade level

High school or above

12th grade level or above

None

No past relevant work experience

Unskilled

Consists of simple duties requiring little to no

judgment that can be learned on the job in 30

days or less

Semiskilled or skilled with no

transferable skills

Semiskilled work requires some skills, does

not require complex duties, and takes 1-6

months to learn; skilled work consists of

skilled job functions, requires good cognitive

functioning, and takes over 6 months to learn

Semiskilled or skilled with

transferable skills

Transferable skills result from skilled or

semiskilled past relevant work that can be

applied in other work within the individual’s

RFC

Source: Appendix 2 to Subpart P of Part 404, 20 C.F.R.; SSA, POMS, “DI 25001.001 Medical and Vocational

Quick Reference Guide,” January 3, 2025, https://secure.ssa.gov/poms.nsf/lnx/0425001001.

Notes:

a. SSA has special rules for individuals who are closely approaching retirement age (age 60 or older) and

individuals who are age 65 and older. See 20 C.F.R. §§404.1563(e), 404.1568(d)(4), 416.963(e), and

416.968(d)(4) and SSA, POMS, “DI 25015.025 Evaluation of Disability and Blindness in Initial Claims for

Individuals Aged 65 or Older—SSR 03-3p,” June 26, 2020, https://secure.ssa.gov/apps10/poms.nsf/lnx/

0425015025.

b. In some cases, SSA may find that age is a more limiting factor for younger individuals who are ages 45-49.

See 20 C.F.R. §§404.1563(c) and 404.963(c).

c. Following a 2019 final rule, SSA no longer considers inability to communicate in English when determining

an individual’s education level. For example, under SSA’s regulations, individuals are considered illiterate if

they are unable to read or write a simple message in any language, are considered to have marginal

education if they have completed formal schooling at a sixth-grade level or below in any country, and so on.

d. SSA considers work experience from past relevant work. Past relevant work is work that (1) was done

within the past five years, (2) was substantial gainful activity, (3) was done long enough for the individual to

learn to do it, and (4) was not started and stopped in fewer than 30 calendar days. SSA used to consider

75 20 C.F.R. §§404.1568 and 416.968; SSA, POMS, “DI 25015.017 Transferability of Skills Assessment Policy,”

November 17, 2023, https://secure.ssa.gov/poms.nsf/lnx/0425015017.

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past relevant work to be work that an individual did within the past 15 years until a rule change, which took

effect on June 22, 2024, shortened the lookback period to five years and added the 30-day minimum

requirement. See SSA, “Intermediate Improvement to the Disability Adjudication Process, Including How

We Consider Past Work,” 89 Federal Register 27653, April 18, 2024, https://www.federalregister.gov/d/

2024-08150; and SSA, “Intermediate Improvement to the Disability Adjudication Process, Including How

We Consider Past Work,” 89 Federal Register 48138, June 5, 2024, https://www.federalregister.gov/d/202412285.

The Medical-Vocational Guidelines

To make determinations about whether individuals are functionally and vocationally able to do

any other work that exists in significant numbers in the national economy, the DDS applies the

medical-vocational guidelines specified in SSA’s regulations. The medical-vocational guidelines

were established in a 1978 SSA rulemaking to help ensure the “soundness and consistency” of

disability determinations involving vocational considerations.76 The guidelines consist of the

grids and guidance on an individual’s ability to adjust to other work (i.e., when the grids serve as

a framework).77 They are based on the third edition of the DOT and the SCO supplement, both of

which were published in the 1960s.78

The Grids

SSA’s grids contain rules specifying certain age, education, and work experience combinations

(i.e., vocational factor combinations) for selected exertional RFCs that direct determinations of

disability.79 When the grids direct a determination, it means that they support a conclusion as to

whether a significant number of jobs (in one or more occupations) exist that the individual can

adjust to given his or her vocational factors and RFC.80 In other words, for an individual with a

combination of vocational factors and exertional abilities that exactly matches one of the grid

rules, the grids will determine whether there are a significant number of jobs in the national

economy that the individual can perform and, thus, whether he or she is disabled.

Three separate grids exist to evaluate individuals whose exertional RFCs are limited to (1)

sedentary work, (2) light work, and (3) medium work. Each individual grid contains various

numbered rules. Each of the numbered rules within a given grid specifies a combination of age,

education, and work experience and a corresponding “decision” of disabled or not disabled based

on that combination.81

In general, under SSA’s rules, older individuals who have little education and work experience are

more likely to be awarded benefits than are younger individuals or those who have more

education or work experience. For example, under rule 201.01, the grids direct a determination of

disabled for an individual whose RFC is limited to sedentary work and who is of advanced age,

76 SSA, “Rules for Adjudicating Disability Claims in Which Vocational Factors Must Be Considered,” 43 Federal

Register 55349, November 28, 1978, https://archives.federalregister.gov/issue_slice/1978/11/28/55346-55381.pdf.

77 SSA, POMS, “DI 25025.001 The Medical-Vocational Guidelines,” March 6, 2024, https://secure.ssa.gov/poms.nsf/

lnx/0425025001. For more information on the Medical-Vocational Guidelines see also SSA, Vocational Expert

Handbook, pp. 26-31.

78 20 C.F.R. §§404.1569 and 416.969. See also SSA, “Rules for Adjudicating Disability Claims in Which Vocational

Factors Must Be Considered,” p. 55352; and OIDAP, Content Model and Classification Recommendations, p. 8.

79 Appendix 2 to Subpart P of Part 404, 20 C.F.R. The grids do not specify every possible combination of exertional

RFC and vocational factors.

80 Appendix 2 to Subpart P of Part 404, 20 C.F.R., and SSA, POMS, “DI 25025.001 The Medical-Vocational

Guidelines.”

81 Appendix 2 to Subpart P of Part 404, 20 C.F.R., and SSA, POMS, “DI 25025.001 The Medical-Vocational

Guidelines.”

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has limited or less education, and has unskilled or no work experience. In contrast, under rule

201.03, the grids direct a determination of not disabled for an individual whose RFC is limited to

sedentary work and who is of advanced age, has limited or less education, and has skilled or

semiskilled work experience and transferable skills. Under rule 201.23, the grids also direct a

determination of not disabled for an individual whose RFC is limited to sedentary work and who

is age 18-44, is illiterate, and has unskilled or no work experience (Table 4).82

Table 4. Selected Medical-Vocational Grid Rules Used in

SSA Adult Disability Determinations

Rule

Residual

Functional

Capacity

Age

Education

Previous

Work

Experience

Decision

201.01

Sedentary worka

Advanced age

(55 or older)

Limitedb or less

Unskilledc or

none

Disabled

201.03

Sedentary work

Advanced age

(55 or older)

Limited or less

Skilled or

semiskilled—

skills

transferabled

Not disabled

201.23

Sedentary work

Younger (age

18-44)

Illiteratee

Unskilled or

none

Not disabled

Source: CRS based on Table I in Appendix 2 to Subpart P of Part 404, 20 C.F.R.

Notes:

a. Sedentary work involves occasionally lifting no more than 10 pounds at once and mostly involves sitting,

though it may occasionally require walking and standing. See 20 C.F.R. §§404.1567 and 416.967 and SSA,

POMS, “DI 25001.001 Medical and Vocational Quick Reference Guide,” January 3, 2025,

https://secure.ssa.gov/poms.nsf/lnx/0425001001.

b. Limited education generally means that an individual has completed formal schooling in any country at a 7 th11th grade level. See 20 C.F.R. §§404.1564 and 416.964 and SSA, POMS, “DI 25015.010 Education as a

Vocational Factor,” August 6, 2020, https://secure.ssa.gov/poms.nsf/lnx/0425015010.

c. Unskilled work experience consists of simple duties that require little to no judgment and can be learned on

the job in 30 days or less. See 20 C.F.R. §§404.1568 and 416.968 and SSA, POMS, “DI 25001.001 Medical

and Vocational Quick Reference Guide.”

d. Semiskilled work experience requires some skills, does not require complex duties, and takes one to six

months to learn. Skilled work experience consists of skilled job functions, requires “good” cognitive

functioning, and takes over six months to learn. Transferable skills result from skilled or semiskilled work

experience that can be applied in other work within an individual’s residual functional capacity. See 20 C.F.R.

§§404.1568 and 416.968; SSA, POMS, “DI 25015.015 Work Experience as Vocational Factor,” July 5, 2024,

https://secure.ssa.gov/poms.nsf/lnx/0425015015; and SSA, POMS, “DI 25015.017 Transferability of Skills

Assessment Policy,” November 17, 2023, https://secure.ssa.gov/poms.nsf/lnx/0425015017.

e. Illiterate means that an individual is unable to read or write a simple message in any language. See 20 C.F.R.

§§404.1564 and 416.964, and SSA, POMS, “DI 25015.010 Education as a Vocational Factor.”

SSA’s regulations recognize that a certain number of unskilled occupations exist at each of the

three exertional levels addressed in the grids, with each occupation consisting of many jobs in the

national economy. The number of unskilled occupations determined to exist at a given exertional

level is considered the occupational base. SSA recognizes about 200 unskilled sedentary

occupations; 1,600 unskilled light and sedentary occupations; and 2,500 medium, light, and

sedentary unskilled occupations in the national economy.83 These unskilled occupation numbers

82 Appendix 2 to Subpart P of Part 404, 20 C.F.R.

83 Appendix 2 to Subpart P of Part 404, 20 C.F.R.

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were based on the SOC supplement to the third edition of the DOT, which was published in

1966.84 The occupational base for an individual with a given exertional RFC may be widened or

narrowed after considering the individual’s vocational factors. When the grids direct a

determination of not disabled, it means that according to SSA, the occupational base is

sufficiently large to allow the individual to adjust to other work—that is, a significant number of

jobs exists in the national economy that the individual can perform given his or her RFC, age,

education, and work experience.85

Because grid rules do not exist for every possible combination of RFC and vocational factors,

they do not direct a determination in every case. For example, the grids generally cannot direct

determinations for individuals who are not capable of performing the full range of work at a given

exertional level (i.e., whose RFC is between levels) or for individuals with only nonexertional

limitations.86

The Grids as a Framework

When an individual’s functional and vocational criteria do not exactly match a grid rule and, thus,

no specific grid rule directs a determination, the grids instead serve as a framework to guide

decisionmaking, along with SSA’s regulations and policies.87 For example, the DDS may need to

use the grids as a framework if an individual’s RFC indicates that he or she cannot perform the

full range of work at a given exertional level specified in the rules (i.e., his or her RFC is between

levels). Because the individual’s functional criteria would not exactly match a grid rule in such a

case, per SSA’s regulations, the DDS cannot use the grids to direct a determination.88

Additionally, because the grids are expressed only in terms of exertional capabilities, they do not

direct determinations for individuals with impairments that cause only nonexertional limitations.

In the latter cases, the grids are used as a framework for making individualized determinations.

According to SSA’s policies, the grids are used as a framework more often than they are used to

direct a determination.89

When the grids are used as a framework, SSA’s rules do not specify whether a significant number

of jobs exists that the individual is functionally and vocationally able to do. According to SSA’s

policies, in such a framework decision the DDS can generally show that an individual can adjust

to other work (and therefore, is not disabled) by citing three non-isolated occupations that the

individual could do given his or her RFC, age, education, and work experience.90 Isolated

84 Appendix 2 to Subpart P of Part 404, 20 C.F.R, and SSA, “Rules for Adjudicating Disability Claims in Which

Vocational Factors Must be Considered,” 43 Federal Register 55349, November 28, 1978, p. 55352,

https://archives.federalregister.gov/issue_slice/1978/11/28/55346-55381.pdf.

85 Appendix 2 to Subpart P of Part 404, 20 C.F.R.; SSA, “SSR 83-10: Titles II and XVI: Determining Capability to do

Other Work—The Medical-Vocational Rules of Appendix 2,” https://www.ssa.gov/OP_Home/rulings/di/02/SSR83-10di-02.html; SSA, POMS, “DI 25025.005 Using the Medical-Vocational Guidelines,” June 21, 2024,

https://secure.ssa.gov/poms.nsf/lnx/0425025005.

86 Appendix 2 to Subpart P of Part 404, 20 C.F.R. In cases where individuals have impairments that result in both

exertional and nonexertional limitations, the grids are generally used as a framework unless a grid rule directs a

determination of disabled based on the individual’s exertional limitations alone. See 20 C.F.R. §§404.1569a(d) and

416.969a(d), and SSA, POMS, “DI 25025.020 Applying the Medical-Vocational Rules When the Claimant Has

Exertional and Nonexertional Limitations,” March 6, 2024, https://secure.ssa.gov/poms.nsf/lnx/0425025020.

87 SSA, POMS, “DI 25025.005 Using the Medical-Vocational Guidelines”; and SSA, POMS, “DI. 25025.030 Support

for a Framework ‘Not Disabled’ Determination,” January 2, 2024, https://secure.ssa.gov/poms.nsf/lnx/0425025030.

88 Appendix 2 to Subpart P of Part 404, 20 C.F.R.

89 SSA, POMS, “DI 25025.005 Using the Medical-Vocational Guidelines.”

90 SSA, POMS, “DI. 25025.030 Support for a Framework ‘Not Disabled’ Determination.” Under certain circumstances,

(continued...)

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occupations are those containing jobs that “exist only in very limited numbers in relatively few

locations outside of the region” where the individual lives.91 SSA considers the DOT to be a

reliable source for determining occupations that exist in the national economy and their

requirements, along with certain other sources.92 SSA may also seek the expertise of vocational

specialists or experts in determining work that individuals with particular functional capabilities

could perform or other vocational issues.93 Under SSA’s policy guidance, if the DDS relies on

certain DOT occupations to support a framework determination that an individual is not disabled,

the DDS is directed to obtain supporting evidence from a vocational specialist.94

Table 5 illustrates when SSA’s grid rules direct a determination and when they instead serve as a

framework for an individualized determination.

Table 5. Applicability of SSA’s Grid Rules in Adult Initial Disability Claims

If…

•

The individual’s impairment causes only

exertional limitations or restrictions AND

•

The individual’s combination of exertional

RFC and vocational factors (i.e., age,

education, work experience) exactly matches

a grid rule

•

The individual’s impairment causes only

nonexertional limitations or restrictions OR

•

The individual’s impairment causes a

combination of exertional and nonexertional

limitations or restrictionsa OR

•

The individual’s RFC is between exertional

levels OR

•

The individual’s combination of RFC and

vocational factors do not exactly match a grid

rule

Then…

The grids direct a determination of disabled or not

disabled for that individual.

The grids are used as a framework along with SSA’s

regulations and policies to make an individualized

determination of disabled or not disabled for that

individual.

Source: Appendix 2 to Subpart P of Part 404, 20 C.F.R.; SSA, POMS, “DI 25025.005 Using the MedicalVocational Guidelines,” June 21, 2024, https://secure.ssa.gov/poms.nsf/lnx/0425025005; SSA, POMS, “DI.

25025.010 Using Rule 204.00 as a Framework for a Determination,” March 6, 2024, https://secure.ssa.gov/

poms.nsf/lnx/0425025010.

Notes:

a. In cases where an individual has both exertional and nonexertional limitations, the grids are generally used

as a framework unless a grid rule applies that directs a determination of disabled based on the individual’s

SSA’s policies specify other ways that a DDS can support a framework determination that an individual can do other

work, such as by citing an applicable Social Security ruling.

91 20 C.F.R. §§404.1566(b) and 416.966(b) and SSA, “Isolated Occupations We Will Not Use to Support a ‘Not

Disabled’ Finding at Step Five of the Sequential Evaluation Process,” June 22, 2024, https://secure.ssa.gov/apps10/

reference.nsf/links/06212024021759PM.

92 20 C.F.R. §§404.1566 and 416.966.

93 20 C.F.R. §§404.1566 and 416.966; SSA, POMS, “DI 25003.001 Vocational Specialists”; SSA, “SSR 24-3p: Titles

II and XVI: Use of Occupational Information and Vocational Specialist and Vocational Expert Evidence in Disability

Determinations and Decisions,” January 6, 2025, https://www.ssa.gov/OP_Home/rulings//di/02/SSR2024-03-di02.html; SSA, “Social Security Ruling 24-3P: Use of Occupational Information and Vocational Specialist and

Vocational Expert Evidence in Disability Determinations and Decisions: Reference Materials,” https://www.ssa.gov/

appeals/public_experts/SSR_24-3p.pdf.

94 SSA, “Guidance Regarding the Citation of Certain Occupations at Step Five of the Sequential Evaluation Process,”

January 6, 2025, https://secure.ssa.gov/apps10/reference.nsf/links/01062025092030AM.

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exertional limitations alone. See 20 C.F.R. §§404.1569a(d) and 416.969a(d) and SSA, POMS, “DI 25025.020

Applying the Medical-Vocational Rules When the Claimant Has Exertional and Nonexertional Limitations,”

March 6, 2024, https://secure.ssa.gov/poms.nsf/lnx/0425025020.

Concerns Raised About SSA’s Continued Reliance

on the DOT for Disability Evaluation

Congress, courts, and others have raised concerns about SSA’s continued reliance on the DOT

when evaluating disability.95

First, some have raised concerns that the occupational information in the DOT does not reflect the

current U.S. labor market. DOL replaced the DOT with a new database of occupational

information in 1998—the Occupational Information Network (O*NET)—and no longer updates

the DOT.96 Some occupations in the DOT were most recently updated in 1991, but most of the

occupations were last updated in 1977.97 A BLS publication notes that the DOT “emerged in an

industrial economy and emphasized blue-collar jobs” and “its usefulness waned as the economy

shifted toward information and services and away from heavy industry.”98 A 2012 Senate report

expressed concern that disability benefits were being awarded based on outdated DOT

information that “does not reflect current labor market trends or jobs in the national economy.”99

The DOT includes occupations that SSA considers to no longer exist in significant numbers (i.e.,

isolated occupations) and may not include other occupations that do exist today. Moreover, the

occupational descriptions in the DOT may not reflect the requirements and demands of

occupations as they are currently performed. In June 2024, SSA identified 114 of the over 12,000

DOT occupations to be isolated and therefore to not exist in significant numbers in the U.S.

economy.100 For example, SSA now considers the DOT occupations of photoradio operator (DOT

Code 193.362-010), embalmer apprentice (DOT Code 338.371-010), and reptile farmer (DOT

Code 413.161-014) to be isolated.101 Around the same time, SSA identified another 13 DOT

95 For example, see U.S. Congress, Senate Committee on Homeland Security and Governmental Affairs, Permanent

Subcommittee on Investigations, Social Security Disability Programs: Improving the Quality of Benefit Award

Decisions, Minority Staff Report, 112th Cong., 2nd sess., September 13, 2012, p. 95, https://www.govinfo.gov/content/

pkg/CHRG-112shrg76068/pdf/CHRG-112shrg76068.pdf#page=103; OIDAP, Content Model and Classification

Recommendations for the Social Security Administration, pp. 15-23; SSA, Office of Inspector General (OIG), The

Social Security Administration’s Efforts to Develop Its Own Source of Occupational Information for Use in Its

Disability Programs, June 2018, p. 3, https://oig-files.ssa.gov/audits/full/A-01-15-15035.pdf; and Kevin Liebkemann,

“Job Incidence Numbers in Social Security Disability Claims: A Case Study and Analysis,” Journal of the National

Association of Administrative Law Judiciary, vol. 44, no. 2 (May 15, 2024), p. 26 and footnote 47,

https://digitalcommons.pepperdine.edu/cgi/viewcontent.cgi?article=1718&context=naalj.

96 DOL, “Status of the Dictionary of Occupational Titles; Use in Social Security Disability Adjudications,”

https://www.dol.gov/agencies/oalj/topics/libraries/LIBDOT.

97 Less than 20% of DOT occupations were updated in 1991. See U.S. Government Accountability Office (GAO),

Modernized SSA Disability Programs: Progress Made, but Key Efforts Warrant More Management Focus, GAO-12420, June 2012, p. 6, footnote 14, https://www.gao.gov/assets/gao-12-420.pdf.

98 Matthew Mariani, “Replace with a Database: O*NET Replaces the DOT,” Occupational Outlook Quarterly, Spring

1999, p. 3, https://www.bls.gov/careeroutlook/1999/Spring/art01.pdf.

99 U.S. Congress, Senate Committee on Homeland Security and Governmental Affairs, Permanent Subcommittee on

Investigations, Social Security Disability Programs: Improving the Quality of Benefit Award Decisions, Minority Staff

Report, 112th Cong., 2nd sess., September 13, 2012, p. 95, https://www.govinfo.gov/content/pkg/CHRG-112shrg76068/

pdf/CHRG-112shrg76068.pdf#page=103.

100 SSA, “Social Security Updates Occupations List Used in Disability Evaluation Process,” press release, June 24,

2024, https://www.ssa.gov/news/press/releases/2024/#6-2024-2.

101 SSA, “Isolated Occupations We Will Not Use to Support a ‘Not Disabled’ Finding at Step Five of the Sequential

Evaluation Process.”

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occupations “whose continued widespread existence multiple courts have questioned” and

therefore are now subject to “heightened evidentiary and articulation requirements” if used to

support a framework decision that an individual is not disabled.102 Examples of these DOT

occupations are addresser (DOT Code 209.587-101), cutter-and-paster (DOT Code 249.587-014),

and nut sorter (DOT Code 521.687-086).103

Second, the DOT was originally designed as a job placement tool, and, as such, some have raised

concerns that it does not contain all the information SSA may need for disability adjudication.104

For example, the DOT does not contain information on certain nonexertional requirements of

occupations (e.g., mental and cognitive demands). Given the changing nature of work, an

independent advisory panel chartered by SSA in 2008 noted the increasing importance of

capturing information on the mental and cognitive demands of occupations to “reduce

adjudicative judgment” in SSA disability evaluation.105

Third, some have raised concerns that the DOT does not easily crosswalk to other federal

occupational sources that contain more updated occupational information or job numbers. Federal

statistical agencies that publish occupational data do not use DOT codes. Instead, these agencies

use the federally mandated Standard Occupational Classification (SOC) system to classify

workers and jobs into occupational categories. The SOC system classifies jobs in a more

aggregated manner than the DOT does—there are 867 SOC codes, compared to over 12,000 DOT

codes.106 In other words, a single SOC code may contain several DOT codes, and thus

information reported by SOC code (e.g., employment estimates) cannot be directly applied to

DOT codes. SSA does not specify an approach that adjudicators should use to estimate the

number of jobs that exist within a particular DOT code.107 And though SSA has recently identified

certain DOT occupations that it considers isolated, it does not otherwise define a threshold for

what constitutes a significant number of jobs.108 Some courts have previously considered whether

job numbers cited by SSA for a given DOT code are credible or if they represent a significant

number of jobs based on which to deny disability benefits.109

102 SSA, “Guidance Regarding the Citation of Certain Occupations at Step Five of the Sequential Evaluation Process.”

103 SSA, “Guidance Regarding the Citation of Certain Occupations at Step Five of the Sequential Evaluation Process.”

104 DOL, Dictionary of Occupational Titles (4th Ed., Rev. 1991) – Appendix D, available at https://www.dol.gov/

agencies/oalj/PUBLIC/DOT/REFERENCES/DOTAPPD, and OIDAP, Content Model and Classification

Recommendations for the Social Security Administration, pp. 15-23.

105 OIDAP, Content Model and Classification Recommendations for the Social Security Administration, p. 40.

106

U.S. Bureau of Labor Statistics (BLS), “Standard Occupational Classification,” https://www.bls.gov/soc/.

107 SSA, “SSR 24-3p: Titles II and XVI: Use of Occupational Information and Vocational Specialist and Vocational

Expert Evidence in Disability Determinations and Decisions,” January 6, 2025, https://www.ssa.gov/OP_Home/rulings/

di/02/SSR2024-03-di-02.html; and SSA, “Guidelines for Using Occupational Information in Electronic Tools,” January

6, 2025, https://secure.ssa.gov/apps10/reference.nsf/links/01062025085235AM.

108 SSA, “Isolated Occupations We Will Not Use to Support a ‘Not Disabled’ Finding at Step Five of the Sequential

Evaluation Process”; SSA, “SSR 24-3p: Titles II and XVI”; SSA, “Guidelines for Using Occupational Information in

Electronic Tools”; SSA, Office of Hearings Operations, Office of the Chief Administrative Law Judge, Vocational

Expert Handbook, p. 44.

109 SSA, OIG, The Social Security Administration’s Efforts to Develop Its Own Source, p. 3; and Liebkemann, “Job

Incidence Numbers in Social Security Disability Claims,” p. 26 and footnote 47.

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SSA’s Occupational Information System (OIS)

Project

SSA undertook the OIS project to develop a new, tailored source of updated occupational

information that would satisfy its legal, programmatic, and technical requirements.110

SSA had previously explored whether existing occupational sources could replace the DOT for

disability evaluation. SSA assessed whether it could adopt the O*NET in disability evaluations

but determined that the O*NET did not meet SSA’s adjudicative needs.111 For example, O*NET

did not provide sufficiently detailed information about the physical demands of occupations or

any information about the mental demands of occupations.112 SSA further concluded that other

existing occupational information systems would also not provide enough information for its

disability determination purposes.113

At the outset of the OIS project in 2008, SSA chartered an independent Occupational Information

Development Advisory Panel (OIDAP) to make recommendations “regarding the type of

occupational information that SSA should collect and the manner in which occupations should be

grouped that best serves disability evaluation.”114 OIDAP made a series of recommendations,

including the following:

The creation of a new occupational information system is needed to replace the [DOT] for

SSA’s disability adjudication system. The OIS must include: a) occupations aggregated at

a level to support individualized disability assessment; b) a cross-walk to the [SOC]; c)

precise occupationally-specific data; d) core work activities; e) minimum levels of

requirements needed to perform work; f) observable and deconstructed measures; g) a

manageable number of data elements; h) sampling methodology capturing the full range of

work; i) inter-rater agreement justifying data inference; j) data collection of high quality

data; k) valid, accurate, and reproducible data; l) whether core work activities could be

performed in alternative ways; and, m) terminology that is consistent with medical practice

and human function.115

In 2011, SSA outlined its approach for a new OIS with a staged rollout initially anticipated in

FY2016.116 In FY2012, SSA entered into an interagency agreement with BLS to test whether BLS

110 SSA, Social Security Administration’s Legal, Program, and Technical/Data Occupational Information

Requirements, February 2009, p. 2, https://web.archive.org/web/20170829021115/https://www.ssa.gov/oidap/

Documents/WEBFORMATED-081009—SSA%20Legal%20Program%20and%20Technical%20Data.pdf.

111 Nancy T. Tippins and Margaret L. Hilton, eds., A Database for a Changing Economy: Review of the Occupational

Information Network (O*NET) (National Academies Press, 2010), p. 160, https://nap.nationalacademies.org/catalog/

12814/a-database-for-a-changing-economy-review-of-the-occupational; SSA, OIG, Job Information Used in the Social

Security Administration’s Disability Claims Adjudication Process, November 2010, pp. 3-4, https://oig-files.ssa.gov/

audits/full/A-01-10-21024_7.pdf; SSA, Responses to Questions for the Record, U.S. House of Representatives,

Committee on Appropriations, Subcommittee on the Departments of Labor, Health, and Human Services, Education,

and Related Agencies, Hearing on “Departments of Labor, Health, and Human Services, Education, and Related

Agencies Appropriations for 2011, 111th Cong., 2nd Sess., March 4, 2010, pp. 450-451, https://www.govinfo.gov/

content/pkg/CHRG-111hhrg58234/pdf/CHRG-111hhrg58234.pdf.

112 SSA, “Occupational Information System Project FAQ’s”; and GAO, SSA Disability Programs: Fully Updating

Disability Criteria Has Implications for Program Design, GAO-02-919T, July 11, 2002, p. 11, https://www.gao.gov/

assets/gao-02-919t.pdf.

113 SSA, Occupational Information System Fiscal Year 2011 Research and Development Plan, footnote 8.

114 OIDAP, Charter, January 15, 2009, p. 1, https://web.archive.org/web/20170826090457/https://www.ssa.gov/oidap/

Documents/FINAL—OIDAP%20CHARTER%20COSS%20&%20DATED%20OIDAPCharter.pdf.

115 OIDAP, Content Model and Classification Recommendations, p. 57.

116 SSA, Occupational Information System Fiscal Year 2011 Research and Development Plan, p. 53.

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could use its National Compensation Survey infrastructure to capture the new occupational

information that SSA needed.117 After several years of preliminary testing, BLS began the first

year of data collection for the new Occupational Requirements Survey (ORS) in September

2015.118 SSA intends the ORS to be the main source of OIS’s information, supplemented by

certain data from other sources.119

Occupational Requirements Survey (ORS)

ORS provides SOC-based survey information on occupations in the national economy, including

the physical demands; environmental conditions; education, training, and experience

requirements; and cognitive and mental requirements of occupations.120 ORS is funded by SSA

and fielded by BLS.121

BLS field economists periodically collect ORS occupational data from a sample of public and

private sector establishments and occupations.122 Each ORS data collection period is referred to

as a “wave.” During a wave, multiple annual samples are collected and combined to produce final

estimates for the wave. Preliminary ORS estimates on a subset of occupations are generally

published each year. As additional annual samples within a wave become available, the

preliminary dataset is updated to incorporate the new information. Once all the samples in a wave

have been collected and published, the estimates are considered final for that wave.123

Following several years of preliminary testing, BLS began the first wave of ORS data collection

in FY2015. The first wave ended in FY2018, and BLS published final data for that wave in

FY2019. The first wave of ORS did not include questions about the mental and cognitive

requirements of occupations, which SSA and BLS were still developing and testing. BLS began

the second wave of ORS data collection in FY2018.124

The second wave used an updated sample design to capture requirements for more occupations

and included new questions related to the mental and cognitive requirements of occupations. The

second wave ended in FY2023, and BLS published final data from that wave in FY2024.125

BLS started the third wave of ORS data collection in FY2023 and published preliminary data on a

subset of occupations in FY2025. BLS began the third year of data collection for the third wave

of ORS in FY2025.126 SSA has since collaborated with BLS to extend the third wave of ORS data

collection to eight years “to reduce survey administrative costs.”127

117 SSA, “Occupational Information System (OIS) Project,” https://www.ssa.gov/disabilityresearch/

occupational_info_systems.html?ab=0.

118 SSA, “Occupational Information System (OIS) Project.”

119 SSA, “Occupational Information System (OIS) Project.”

120 BLS, “Occupational Requirements Survey: Overview,” https://www.bls.gov/opub/hom/ors/home.htm; and BLS,

“Classifying Jobs: From the Dictionary of Occupational Titles (DOT) to the Standard Occupational Classification

(SOC),” https://www.bls.gov/ors/factsheet/classifying-jobs.htm.

121 BLS, FY2025 Congressional Budget Justification, p. 49, https://www.dol.gov/sites/dolgov/files/general/budget/

2025/CBJ-2025-V3-01.pdf.

122 BLS, “Occupational Requirements Survey: Design,” https://www.bls.gov/opub/hom/ors/design.htm.

123 BLS, “Occupational Requirements Survey: Presentation,” https://www.bls.gov/opub/hom/ors/presentation.htm.

124 SSA, “Occupational Information System (OIS) Project.”

125 SSA, “Occupational Information System (OIS) Project.”

126 SSA, “Occupational Information System (OIS) Project”; and SSA, Justification of Estimates for Appropriations

Committees, FY 2025, p. 78, https://www.ssa.gov/budget/assets/materials/2025/FY25-JEAC.pdf.

127 SSA, “Occupational Information System (OIS) Project.”

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ORS captures information not previously available from the DOT, such as the mental and

cognitive requirements of occupations. Additionally, ORS classifies occupations by SOC code

rather than by DOT code, allowing matching to other occupational sources that contain additional

SOC-based data that SSA may use in disability evaluation, such as employment estimates.

Additionally, BLS plans to regularly update the ORS. In contrast, DOL has not updated the DOT

since 1991. Table 6 compares selected DOT and ORS attributes.

Table 6. Comparison of Selected DOT and ORS Attributes

Dictionary of Occupational

Titles (DOT)

Occupational Requirements

Survey (ORS)

Available Occupational Information

Physical demands, environmental

conditions, specific vocational

preparation (SVP)

Physical demands, environmental

conditions, SVP, cognitive and

mental requirements

Occupational Classification System

DOT

Standard Occupational

Classification (SOC)

Number of Occupational Groups

Over 12,000 DOT titles

Over 800 SOC codes at the most

detailed level; ORS Wave 2 data are

available for about 500 of these

SOC codes

Job Numbers by Occupational

Group

Not directly available, though some

federal statistical agencies may

produce crosswalks to SOC-based

estimates; private companies may

also produce estimates using

proprietary methods

Number of workers by SOC code

is available from the Occupational

Employment and Wage Statistics

program

Update Schedule

No longer updated; last updated in

1991

Is to be updated on a continuous

cycle (i.e., “wave”); preliminary data

on a subset of occupations are to

be released each year; final wave

data are to be released roughly

every 5-10 years; preliminary Wave

3 data on a subset of occupations

were released in November 2024

Attribute

Source: CRS based on BLS, “Classifying Jobs: From the Dictionary of Occupational Titles (DOT) to the

Standard Occupational Classification (SOC),” https://www.bls.gov/ors/factsheet/classifying-jobs.htm; and SSA,

“Occupational Information System (OIS) Project,” https://www.ssa.gov/disabilityresearch/

occupational_info_systems.html.

Status of OIS

Despite over a decade of work on the project, to date, SSA has not fully implemented the new

OIS. According to SSA’s OIS webpage, the initial goal of OIS was to support “current policy with

minimal change.”128 But SSA later “determined that larger changes to policy would be

necessary.”129 Because of this, SSA states that to implement the new OIS it first needs (1) secondwave five-year production data from BLS, (2) the Vocational Information Tool (VIT), and (3)

new regulations and revised subregulatory guidance.130 BLS published final second-wave ORS

data in February 2024. The VIT is a web-based platform that SSA has been developing to house

128 SSA, “Occupational Information System (OIS) Project.”

129 SSA, “Occupational Information System (OIS) Project.”

130 SSA, “Occupational Information System (OIS) Project.”

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and operationalize occupational information from the ORS and other sources.131 According to

SSA, it paused work on the VIT in FY2021 to develop new vocational policies.132 Because the

concepts in the DOT form the basis for SSA’s existing medical-vocational regulations and

policies, to fully implement OIS, SSA would need to revise its regulations and policy guidance to

reflect the new ORS information.133

In its FY2025 and FY2026 budget justifications, SSA stated that it would use the second-wave

ORS data to conduct an OIS-related rulemaking.134 According to a February 2025 Government

Accountability Office (GAO) report, SSA “has not prioritized the rule and policy changes [it]

says are needed to use updated occupational criteria.”135 SSA included a planned rulemaking on

“Improvements to the Disability Adjudication Process: Sequential Evaluation Process” in the

Spring 2025 Unified Agenda, which “includes proposing policy updates to occupational data

sources and optimizing their use to serve [its] customers and preserve the trust funds.”136 As of

early December 2025, SSA has not issued proposed rules or publicly disclosed an implementation

date for OIS. In the meantime, SSA’s regulations continue to recognize the DOT as a reliable

source of occupational information. In early 2025, SSA issued a policy interpretation ruling

relaxing the requirements for using information from occupational sources other than the DOT in

disability evaluation.137

Considerations for Congress

Adequacy of Information

Congress may consider seeking more information on the status of the OIS project, such as by

holding hearings, submitting letters seeking clarifying information, or requiring SSA to provide

reports. For example, OIS came up in at least four separate hearings during the 118th Congress

and during numerous other hearings in Congresses before that.138 In the past, House and Senate

131 SSA, “Occupational Information System (OIS) Project.”

132 SSA, “Fact Sheet: Occupational Information System Project,” July 2024, https://web.archive.org/web/

20250320043709/https://www.ssa.gov/disabilityresearch/documents/Fact%20Sheet%20%20Occupational%20Information%20System%20Project.pdf. SSA contracted with Northrop Grumman and CGI for

VIT development.

133 SSA, Social Security Administration’s Legal, Program, and Technical/Data Occupational Information

Requirements, pp. 4-5.

134 SSA, Justification of Estimates for Appropriations Committees, FY 2025, p. 78; and SSA, Justification of Estimates

for Appropriations Committees for Fiscal Year 2026, p. 51, https://www.ssa.gov/budget/assets/materials/2026/FY26JEAC.pdf.

135 GAO, High Risk Series: Heightened Attention Could Save Billions More and Improve Government Efficiency and

Effectiveness, GAO-25-107743, February 2025, p. 192, https://www.gao.gov/assets/gao-25-107743.pdf.

136 Regulatory Information Service Center, “Unified Agenda of Federal Regulatory and Deregulatory Actions,” Spring

2025, https://www.reginfo.gov/public/do/eAgendaViewRule?pubId=202504&RIN=0960-AI67. Recent press reports

suggest that SSA may not move forward with this proposed rulemaking. As of the date of this report, SSA has not

officially announced any changes to this planned rulemaking.

137 SSA, “SSR 24-3p: Titles II and XVI”; SSA, Vocational Expert Handbook, p. 44; GAO, High Risk Series:

Heightened Attention Could Save Billions More and Improve Government Efficiency and Effectiveness, p. 193.

138 For example, see U.S. Congress, Senate Committee on Finance, Work and Social Security Benefits, 118th Cong., 2nd

sess., June 18, 2024; U.S. Congress, House Committee on Ways and Means, Subcommittee on Social Security and

Subcommittee on Work and Welfare, Social Security Administration, 118th Cong., 2nd sess., March 21, 2024; U.S.

Congress, Senate Committee on Finance, The President’s FY2025 Social Security Administration Budget, 118th Cong.,

2nd sess., March 20, 2024; and U.S. Congress, House Committee on Ways and Means, Subcommittee on Social

(continued...)

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appropriators have also repeatedly requested that SSA report to Congress on the status of the OIS

project and provide a timeline for its expected implementation. S.Rept. 119-55139 For example,

the Joint Statement of Managers accompanying the Consolidated Appropriations Act of 2012

(P.L. 112-74) directed SSA to report to Congress annually on the status of the OIS project.

However, according to a 2025 GAO report, SSA has not submitted such an annual report to

Congress since 2022.140

SSA provides some information on an OIS project page on its website, which currently includes

high-level information about OIS’s objective and status and a summary of the project’s key

activities from FY2012 to FY2025.141 Also on that webpage, SSA links to an OIS frequently

asked questions webpage.142 SSA has also previously included some information about the OIS

project in its budget justifications.143

Project’s Costs

In July 2024, SSA stated that since FY2012 it had spent about $300 million on ORS development

and data collection and that from FY2017 to FY2020 it spent $8.9 million on VIT

Security, One Million Claims and Growing: Improving Social Security’s Disability Adjudication Process, 118th Cong.,

1st sess., October 26, 2023. Also see for example, U.S. Congress, Senate Committee on Homeland Security and

Governmental Affairs, High-Risk List 2019: Recommendations to Reduce Risk of Waste, Fraud, and Mismanagement

in Federal Programs, 116th Cong., 1st sess., March 6, 2019; U.S. Congress, House Committee on Ways and Means,

Subcommittee on Social Security, Examining Changes to Social Security’s Disability Appeals Process, 115th Cong., 2nd

sess., July 25, 2018; U.S. Congress, House Committee on Ways and Means, Subcommittee on Social Security, Lacking

a Leader: Challenges Facing the SSA After over 5 Years of Acting Commissioners, 115th Cong., 2nd sess., March 7,

2018; U.S. Congress, House Committee on Ways and Means, Determining Eligibility for Disability Benefits:

Challenges Facing the Social Security Administration, 115th Cong., 1st sess., September 6, 2017; U.S. Congress, Joint

Economic Committee, Ensuring Success for the Social Security Disability Insurance Program and Its Beneficiaries,

114th Cong., 1st sess., November 4, 2015; U.S. Congress, House Committee on Oversight and Government Reform,

Examining Ways the Social Security Administration Can Improve the Disability Review Process, 113th Cong., 2nd sess.,

April 9, 2014; U.S. Congress, Committee on Ways and Means, The Challenges Facing the Next Commissioner of

Social Security, 113th Cong., 1st sess., April 26, 2013; U.S. Congress, House Committee on Ways and Means, Fifth in a

Hearing Series on Securing the Future of the Social Security Disability Insurance Program, 112th Cong., 2nd sess.,

September 14, 2012; U.S. Congress, Senate Committee on Homeland Security and Governmental Affairs, Permanent

Subcommittee on Investigations, Social Security Disability Programs: Improving the Quality of Benefit Award

Decisions, 112th Cong., 2nd sess., September 13, 2012; U.S. Congress, Senate Committee on Finance, The Social

Security Administration: Is It Meeting Its Responsibilities to Save Taxpayer Dollars and Serve the Public?, 112th

Cong., 2nd sess., May 17, 2012; and U.S. Congress, House Committee on Ways and Means, Third in a Hearing Series

on Securing the Future of the Social Security Disability Insurance Program, 112th Cong., 2nd sess., March 20, 2012.

139 For example, see SSA, FY 2019 Congressional Justification, p. 125, https://www.ssa.gov/budget/assets/materials/

2019/2019CJ.pdf; SSA, FY 2020 Congressional Justification, p. 121, https://www.ssa.gov/budget/assets/materials/

2020/FY20-JEAC_2.pdf; SSA, FY 2021 Congressional Justification, p. 106, https://www.ssa.gov/budget/assets/

materials/2021/FY21-JEAC.pdf; SSA, FY 2022 Congressional Justification, p. 100, https://www.ssa.gov/budget/assets/

materials/2022/FY22-JEAC.pdf; SSA, Justification of Estimates for Appropriations Committees: Fiscal Year 2023, p.

98, https://www.ssa.gov/budget/assets/materials/2023/FY23-JEAC.pdf; SSA, Justification of Estimates for

Appropriations Committees: Fiscal Year 2024, pp. 100-101, https://www.ssa.gov/budget/assets/materials/2024/FY24JEAC.pdf; SSA, Justification of Estimates for Appropriations Committees, FY 2025, pp. 99-100; U.S. House of

Representatives, Committee on Appropriations, Joint Explanatory Statement accompanying P.L. 118-47, p. 797,

https://www.congress.gov/118/cprt/HPRT55008/CPRT-118HPRT55008.pdf; and U.S. Senate, Committee on

Appropriations, accompanying S. 2587, p. 337, https://www.congress.gov/119/crpt/srpt55/CRPT-119srpt55.pdf.

140 GAO, High Risk Series: Heightened Attention Could Save Billions More and Improve Government Efficiency and

Effectiveness, p. 192. For SSA’s FY2022 report, see SSA, Report on the Occupational Information System Project,

April 13, 2022, https://www.ssa.gov/legislation/FY2021%20OIS%20Report%20to%20Congress.pdf.

141 SSA, “Occupational Information System (OIS) Project.”

142 SSA, “Occupational Information System Project FAQ’s.”

143 Available at SSA, “Budget Estimates,” https://www.ssa.gov/budget.

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development.144 SSA plans to work with BLS to regularly update ORS occupational information

in waves to ensure the information remains current. According to a 2018 SSA Office of Inspector

General (OIG) report, SSA had estimated that each additional wave of ORS data collection would

cost about $167 million.145

SSA pays for its OIS activities from funding provided by Congress each year as part of the annual

appropriations process.146 According to the SSA OIG, if SSA’s budget “is insufficient to cover all

its priorities in any given year, [SSA] might shift the funds from the [OIS] project to its other

priorities in that year.”147 The OIG also stated that if “SSA cannot continually update the [OIS],

its information will become outdated, like some of the DOT’s information.”148

To the extent that Congress views OIS implementation and maintenance as priority workloads for

SSA, Congress may consider providing SSA with dedicated funding for these activities in

amounts based on SSA’s estimated resource needs or what lawmakers deem to be an appropriate

level.

Implementation Timeline

Congress has repeatedly inquired about the status of the OIS project and SSA’s timeline for using

the new OIS in disability determinations. As of early December 2025, SSA has not issued

proposed rules or publicly disclosed an implementation date for OIS.149 SSA included a proposed

rulemaking in the Spring 2025 Unified Agenda that would outline how it will use the new

occupational information in SSDI and SSI disability determinations.150 Until SSA implements the

new OIS, it continues to use the DOT, which becomes increasingly outdated the longer SSA

continues using it.151

Lawmakers may consider enacting OIS implementation requirements. For example, during the

118th Congress, Senator Bill Cassidy and then-Senator Sherrod Brown introduced the Improving

Employment Options for DI Beneficiaries Act (S. 2830), which would have required SSA to,

144 SSA, “Fact Sheet: Occupational Information System Project.” Per SSA’s FY2026 budget justification, SSA

obligated a total of $307.0 million from FY2012 to FY2024 for OIS and VIT. See SSA, Justification of Estimates for

Appropriations Committees for Fiscal Year 2026, p. 54. SSA obligated additional funds for OIS in years before

FY2012. See U.S. Congress, House Committee on Ways and Means, Subcommittee on Social Security, Hearing on the

Challenges of Achieving Fair and Consistent Disability Decisions, 113th Cong., 1st sess., March 20, 2013, p. 90,

https://www.govinfo.gov/content/pkg/CHRG-113hhrg89589/pdf/CHRG-113hhrg89589.pdf. According to SSA, the

VIT cost estimate captured the tool’s total cost up to that date (July 2024).

145 SSA, OIG, SSA’s Efforts to Develop Occupational Information, p. 8.

146 The development of the OIS and VIT is funded from SSA’s research and demonstration budget in the SSI account,

while the salaries of SSA employees are typically funded from the agency’s general administrative budget in the

Limitation on Administrative Expenses account. See SSA, Justification of Estimates for Appropriations Committees for

Fiscal Year 2026, p. 54; and CRS Report R47097, Social Security Administration (SSA): Trends in the Annual

Limitation on Administrative Expenses (LAE) Appropriation.

147 SSA, OIG, SSA’s Efforts to Develop Occupational Information, p. 10.

148 SSA, OIG, SSA’s Efforts to Develop Occupational Information, p. 10.

149 Regulatory Information Service Center, “Unified Agenda of Federal Regulatory and Deregulatory Actions,” Fall

2024, https://www.reginfo.gov/public/do/eAgendaViewRule?pubId=202410&RIN=0960-AI67.

150 Regulatory Information Service Center, “Unified Agenda of Federal Regulatory and Deregulatory Actions,” Spring

2025, https://www.reginfo.gov/public/do/eAgendaViewRule?pubId=202504&RIN=0960-AI67. Recent press reports

suggest that SSA may not move forward with this proposed rulemaking. As of the date of this report, SSA has not

officially announced any changes to this planned rulemaking.

151 SSA, OIG, SSA’s Efforts to Develop Occupational Information, p. 10.

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within one year of the bill’s enactment and every three years after that, use updated BLS data to

determine jobs that exist in the national economy to make certain SSDI disability determinations.

Implications of OIS Implementation for SSDI and SSI Eligibility

Implementation of SSA’s new OIS may change initial or continuing SSDI or SSI eligibility. It is

possible that, relative to current regulations, SSA’s new OIS may make some individuals less

likely to qualify for disability benefits and others more likely to qualify. After OIS

implementation, individuals who would have been allowed benefits under current regulations

may be denied benefits under SSA’s new OIS—for example, because they are unable to do any

DOT occupations but are able to do more modern occupations. Others who would have been

denied disability benefits under current regulations may be allowed disability benefits under

SSA’s new OIS—for example, because they can do only DOT occupations that no longer exist in

significant numbers in the national economy. Still others may be unaffected by the change—they

would have been allowed under both SSA’s current regulations and the new OIS or denied under

both SSA’s current regulations and the new OIS. Overall SSDI and SSI allowances could

increase, decrease, or remain unchanged after OIS implementation. Factors potentially

influencing any such eligibility changes may include, for example, the changing nature of work,

the integration of mental and cognitive demands of occupations into the new OIS, and how SSA

chooses to construct its regulations to implement the new OIS. SSA has not made public any

estimates of the anticipated effects of OIS implementation on SSDI or SSI eligibility. Congress

may seek to further evaluate the potential impact of this planned policy change on disability

program participation.

Author Information

Emma K. Tatem

Analyst in Social Policy

Disclaimer

This document was prepared by the Congressional Research Service (CRS). CRS serves as nonpartisan

shared staff to congressional committees and Members of Congress. It operates solely at the behest of and

under the direction of Congress. Information in a CRS Report should not be relied upon for purposes other

than public understanding of information that has been provided by CRS to Members of Congress in

connection with CRS’s institutional role. CRS Reports, as a work of the United States Government, are not

subject to copyright protection in the United States. Any CRS Report may be reproduced and distributed in

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R48748 · VERSION 1 · NEW

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This is a copy of a public record, reproduced as it was published. It is not legal advice, and it may not be the version a court would rely on. Check the official source before you cite it.

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