Gwyneth Gilbert v. Lands' End, Inc.

In the

United States Court of Appeals

For the Seventh Circuit

____________________

No. 23-3162

GWYNETH GILBERT, et al.,

Plaintiffs-Appellants,

v.

LANDS’ END, INC., et al.,

Defendants-Appellees.

____________________

Appeal from the United States District Court for the

Western District of Wisconsin.

Nos. 3:19-cv-00823 & 3:19-cv-01066 — James D. Peterson, Chief Judge.

____________________

ARGUED NOVEMBER 14, 2024 — DECIDED OCTOBER 23, 2025

____________________

Before JACKSON-AKIWUMI, PRYOR, and MALDONADO,

Circuit Judges.

JACKSON-AKIWUMI, Circuit Judge. Delta Airlines partnered

with outfitter Lands’ End to update Delta employee uniforms.

Lands’ End, working with manufacturers and suppliers

across the world, delivered nearly one hundred different

types of garments to the airline. After donning the new uni-

forms, hundreds of Delta employees complained about

2 No. 23-3162

garment dye leaching onto their property. Many also com-

plained that they experienced a wide array of medical symp-

toms.

Several hundred Delta employees sued Lands’ End. Some

brought breach of warranty claims against the outfitter as in-

tended beneficiaries of the apparel contract Lands’ End had

with Delta. Others brought personal injury claims for the

medical symptoms caused by dye transfer. Discovery en-

sued—the record contained laboratory test results and re-

ports by experts in textile chemistry, epidemiology, toxicol-

ogy, and dermatology. After discovery, the district court

granted Lands’ End summary judgment on the breach of war-

ranty and personal injury claims. Plaintiffs ask this court to

reverse both decisions, but we affirm.

I

Lands’ End partnered with fabric mills and factories over-

seas, including in China, Sri Lanka, and Vietnam, to produce

uniforms for Delta Airlines. The new uniforms were then dis-

tributed to 64,000 Delta employees. Not long after the gar-

ments arrived, complaints started streaming in. Employees

informed Lands’ End that the uniforms transferred dye (or

crocked, as commonly referred to in the textile industry) onto

other surfaces and made them sick. Employees complained of

rashes, itchiness, fatigue, headaches, anxiety, memory issues,

coughing, breathing difficulties, and vocal cord issues soon

after they started wearing the uniforms.

Two groups of Delta employees, the “Gilbert plaintiffs”

and “Andrews plaintiffs,” brought lawsuits against Lands’

End. The five Gilbert plaintiffs filed a putative class action

seeking to recover for the damage the leaching dye caused to

No. 23-3162 3

their property—clothes, accessories, sheets, towels, furnish-

ings, and other items. The Gilbert plaintiffs also sought recov-

ery for breach of express warranties under Delta’s contract

with Lands’ End which stated that the uniforms would be free

of defects in material and workmanship, and that plaintiffs

would be 100% satisfied with them. The Andrews plaintiffs,

comprised of 605 individually named Delta employees,

brought products liability claims against Lands’ End for their

personal injuries. They alleged that the uniforms were defec-

tively manufactured and defectively designed, and that

Lands’ End failed to warn of the defects. Before discovery, the

district court consolidated the two actions into a single case

and set different briefing schedules depending on whether an

issue affected large groups of plaintiffs or individual plain-

tiffs.

After discovery, Lands’ End moved for summary judg-

ment and prevailed across the board. In the outfitters’ motion

for summary judgment on the Andrews plaintiffs’ personal

injury claims, the company argued that plaintiffs presented

no credible expert testimony in support of their contention

that the uniforms were defective or caused their injuries. The

district court granted that motion after excluding three of the

Andrews plaintiffs’ expert opinions. Meanwhile, the Gilbert

plaintiffs and Lands’ End cross-moved for partial summary

judgment on plaintiffs’ claim that the 100% satisfaction guar-

anteed warranty had been breached. The district court again

ruled in favor of Lands’ End.

Both sets of plaintiffs appealed. 1 The Andrews plaintiffs

challenge the district court’s grant of summary judgment to

1 Several of the Gilbert plaintiffs’ requests for relief are not, or are no

longer, on appeal. First, the Gilbert plaintiffs moved for partial summary

4 No. 23-3162

Lands’ End on the personal injury claims. Relatedly, they

challenge the district court’s exclusion of their expert wit-

nesses. The Gilbert plaintiffs challenge the district court’s

grant of summary judgment to Lands’ End on the breach of

warranty claims.

II.

We review grants of summary judgment de novo. Thomp-

son Corrugated Sys., Inc. v. Engico, S.R.L., 111 F.4th 747, 751 (7th

Cir. 2024). Summary judgment is appropriate where “the mo-

vant shows that there is no genuine dispute as to any material

fact and that the movant is entitled to judgment as a matter of

law.” Fed. R. Civ. P. 56(a).

We have two standards of review for questions involving

expert witness testimony. We review the application of Fed-

eral Rule of Evidence 702, which governs the district court in

qualifying expert witnesses, de novo. Chi. Joe’s Tea Room, LLC

v. Vill. of Broadview, 94 F.4th 588, 596 (7th Cir. 2024). But we

review “more specific decisions to admit or exclude expert

testimony—once properly classified as such—for an abuse of

discretion.” Id.; see also Daubert v. Merrell Dow Pharmaceuticals,

Inc., 509 U.S. 579, 592–95 (1993). Thus, “so long as the district

court adhered to Daubert’s requirements, we shall not disturb

the district court’s findings unless they are manifestly

judgment on their claim for breach of the warranty guaranteeing defect-

free uniforms. The district court denied the motion, and the Gilbert plain-

tiffs do not appeal that denial. Second and third, the Gilbert plaintiffs

moved for class certification and summary judgment on their property

damage claims. The district court denied the motions for class certification

and summary judgment. The Gilbert plaintiffs initially appealed the de-

nial of these two motions but announced in their reply brief that they were

withdrawing the appeals. Therefore, we discuss these subjects no further.

No. 23-3162 5

erroneous.” Naeem v. McKesson Drug Co., 444 F.3d 593, 607–08

(7th Cir. 2006) (citation modified).

We begin with the Andrews plaintiffs’ personal injury

claims and end with the Gilbert plaintiffs’ breach of warranty

claims.

A. Personal Injury Claims

The Andrews plaintiffs pursued three products liability

claims in their effort to recover from Lands’ End for their per-

sonal injuries. These three claims were for manufacturing de-

fect, design defect, and failure to warn.

We apply Wisconsin state law to these claims because it is

“the substantive law of the state in which the federal court

sits” in this action based on diversity jurisdiction and because

“there is no dispute over which state’s law applies.”

Kolchinsky v. W. Dairy Transp., LLC, 949 F.3d 1010, 1013 n.2

(7th Cir. 2020) (per curiam).

1. Proof of Defect

To make out any of their personal injury claims, the An-

drews plaintiffs needed to present evidence that the garments

were defective. See Godoy ex rel. Gramling v. E.I. du Pont de

Nemours & Co., 2009 WI 78, ¶ 29 (manufacturing defect claims

require evidence that the offending product “deviate[d] from

the manufacturer’s specifications, and that deviation cause[d]

it to be unreasonably dangerous.”); id. (design defect claims

require evidence that “the design itself is the cause of the un-

reasonable danger”); id. (failure to warn claims require evi-

dence that “an intended use of the product is dangerous, but

the manufacturer did not provide sufficient warning or in-

struction”). Plaintiffs relied on laboratory tests to determine

what, if any, harmful substances the garments contained and

6 No. 23-3162

expert witness testimony to prove defect. We first describe the

results of those tests and then the reliability of the expert wit-

ness testimony interpreting those results.

a. Test Results

Plaintiffs allege that the garments were defective because

they leached harmful chemicals and heavy metals alongside

the dye that crocked onto wearers. Plaintiffs subjected many

of the garments to tests designed to detect dye and chemical

transfer in hopes of proving a defect. These tests had mixed

results. The tested garments scored between 3.5 and 5 (out of

5) for crocking (meaning they did, in fact, crock). Yet, labora-

tory technicians who conducted the crocking tests noted that

all the tested garments “met general industry standards … for

crockfastness.” X-Ray tests measuring chemical transfer es-

tablished that some of the garments transferred fluorine, so-

dium, magnesium, and silicon. The technicians who con-

ducted those tests did not note on the reports whether the

transfer of these chemicals was harmful or common in the in-

dustry.

Other chemical transfer tests found that the garments

“contain[ed] several chemicals that are known to be irritating

and potentially toxic.” One such test found that several gar-

ments contained potentially harmful substances like perfluo-

rooctanoic acid, heavy metals (e.g. antimony, chromium, mer-

cury, etc.), formaldehyde, and bromine.

Worn garments generally contained harmful substances

in higher concentrations than unworn garments. Some data

collection technicians speculated that worn garments had

higher concentrations of these substances because of chemical

No. 23-3162 7

reactions between the garments and deodorants, lotions, per-

fumes, and laundry detergents used by the wearer.

b. Expert Witnesses

As the district court recognized and as the parties do not

dispute, a jury would not be able to determine the existence

of a defect by independently reviewing the test results; expert

witness testimony is necessary to assist. See City of Cedarburg

Light & Water Comm’n v. Allis-Chalmers Mfg. Co., 148 N.W.2d

13, 16–17 (Wis. 1967). To that end, the Andrews plaintiffs pre-

sented three expert witnesses in support of their defect argu-

ment: Dr. Peter J. Hauser (a textile expert), Dr. Fred Apple (a

toxicologist), and Dr. Pamela Scheinman (a dermatologist and

medical expert).

Dr. Hauser opined in his report that the garments were

defective because they “transfer[red] … colorant from the sur-

face of the fabric” to other surfaces like the wearers’ skin and

property. He stated that the garments crocked because Lands’

End employed a dye process that “was improper, inadequate,

defective, and not in compliance with industry standards”

and did not “properly afterwash[] or otherwise scour[]” the

uniforms. Dr. Hauser also confirmed that the garments trans-

ferred fluorine, sodium, magnesium, aluminum, and silicon

when crocking, as the tests showed. Importantly, Dr. Hauser

did not opine on whether, how, or at what concentrations

such chemical transfer would qualify as a defect.

Dr. Hauser’s report was straightforward and definitive.

But during his deposition, he was rather equivocal on the is-

sue of defect when it came to the personal injury claims. Dr.

Hauser did not discuss whether the dye was itself harmful to

human health. He also did not testify whether it was the dye

8 No. 23-3162

as opposed to something else that transferred any of the other

chemicals or heavy metals found in the garments. Rather, Dr.

Hauser stated that the five chemicals listed above (fluorine,

sodium, magnesium, aluminum, and silicon) were routinely

found in garments and were not present at concerning levels

in the tested uniforms. Strikingly, when asked to describe in-

dustry standards for colorfastness, Dr. Hauser seemed to un-

dermine his report’s findings on the inadequacy of the dye

process. Whereas his report stated in absolute terms that the

garments were defective, his testimony was that no broad in-

dustry standards for colorfastness exist. Instead, Dr. Hauser

explained, retailers and consumers together set acceptable

limits during contract negotiations.

Plaintiffs’ toxicology expert, Dr. Fred Apple, reviewed the

lab tests and opined in his report that the garments contained

“elevated and sometimes dangerous levels of” chemicals and

heavy metals. Although Dr. Apple also opined that wearers

were exposed to these substances through transferred dye as

the uniforms crocked, he did not state whether the garments

were defective. Like Dr. Hauser, Dr. Apple’s deposition testi-

mony was more equivocal. When deposed, Dr. Apple testi-

fied that he was not knowledgeable about the permissible lim-

its of any of the substances found in the garments or the path-

ways by which such substances might be transferred from

garment to wearer.

Plaintiffs’ medical expert Dr. Pamela Scheinman, unlike

Drs. Hauser and Apple, did not interpret any of the laboratory

test results. Instead, Dr. Scheinman’s report assumed that

plaintiffs were exposed to harmful chemicals and metals by

wearing the garments and exclusively considered whether

such exposure could cause their personal injuries. In forming

No. 23-3162 9

her opinion, Dr. Scheinman reviewed some plaintiffs’ medical

records, but did not independently examine any plaintiffs.

From this, she concluded that the garments caused plaintiffs’

symptoms. Like the other experts, Dr. Scheinman did not

reach any conclusions about whether the garments were de-

fective.

This evidence, taken together, does not support the con-

clusion that the uniforms were defective. Dr. Hauser’s expert

report comes closest when stating that Lands’ End employed

a defective dye process that caused dye to crock onto wearers’

skin and property. Standing alone, this might have qualified

as admissible expert defect testimony for plaintiff’s property

damage claims. Yet, the report and testimony were not suffi-

cient for the personal injury claims. Dr. Hauser expressly dis-

claimed the opinion that crocking routinely results in the

transfer of fluorine, sodium, magnesium, aluminum and sili-

con. Going even further, he declined to opine on whether

these chemicals were transferred to wearers at concentrations

that could cause injury. In retrospect, this is unsurprising be-

cause Dr. Hauser’s report focused only on the questions

raised by plaintiffs’ property damage claims.

Despite this, plaintiffs argue that Dr. Hauser’s statement

that some garments transferred the five chemicals when

crocking is sufficient to establish defect because the statement

proves the garments were “dangerous to an extent beyond

that which would be contemplated by the ordinary consumer

… with the ordinary knowledge common to the community

as to its characteristics.” Murphy v. Columbus McKinnon Corp.,

2022 WI 109, ¶ 21. This argument is unconvincing because Dr.

Hauser never makes any such finding. Far short of testifying

that the transferred chemicals were dangerous, he testified

10 No. 23-3162

that the five chemicals at issue were commonly found in tex-

tiles and were present at routine concentrations in the gar-

ments. And his report and testimony are entirely silent on the

other chemicals and heavy metals (i.e. perfluorooctanoic acid,

antimony, chromium, mercury, formaldehyde, and bromine)

found in the garments.

Dr. Apple and Scheinman’s reports and testimony are

similarly insufficient to prove defect. Plaintiffs are correct that

these two experts testified that the laboratory tests showed

the garments contained several metals and chemicals. But nei-

ther expert tied the presence of these substances to a defect in

the uniforms. This too is understandable because, as toxicol-

ogy and medical experts, they would not be qualified to opine

on the garment manufacturing process.

In sum, plaintiffs have not demonstrated a genuine factual

dispute as to the existence of a defect. At best, the laboratory

results and expert opinions show that some garments leached

dye, that some garments contained chemicals and heavy met-

als at varying levels, and that some crocking resulted in non-

threatening chemical transfer. None of the experts’ findings

permit a jury to conclude that the hundreds of garments

plaintiffs wore were defective in a manner resulting in the

transfer of toxins.

2. Proof of Causation

As we just discussed, the Andrews plaintiffs’ failure to

present sufficient evidence as to the existence of a defect de-

feats their suit. Tanner v. Shoupe, 596 N.W.2d 805, 811 (Wis. Ct.

App. 1999) (noting that the existence of a defect is a necessary

element of a products liability claim). But their suit encoun-

ters a second obstacle. The record lacks sufficient evidence for

No. 23-3162 11

a jury to find that Lands’ End caused plaintiffs’ personal inju-

ries.

To make out any of the products liability claims asserted

in this case (manufacturing defect, design defect, and failure

to warn), plaintiffs must establish that “the defect was a cause

of the plaintiff’s injuries or damages.” Godoy, 2009 WI 78, ¶ 16

n.7. According to the parties, plaintiffs must prove both gen-

eral and specific causation. 2 General causation asks whether

the toxic substance “had the capacity to cause the harm al-

leged.” C.W. ex rel. Wood v. Textron, Inc., 807 F.3d 827, 831 (7th

Cir. 2015) (citation modified). “Specific causation, by contrast,

examines whether the substance did, in fact, cause the harm

alleged.” Id.

2 The parties misstate the standard. Wisconsin law does not require a

showing of general and specific causation as routinely stated in the com-

mon law. Rather, assuming arguendo that the dye transfer is a valid defect,

plaintiffs were required to present evidence that this defect “was a sub-

stantial factor in causing” their injuries. See Burton v. E.I. du Pont de Nemours

& Co., 994 F.3d 791, 824, 827 (7th Cir. 2021) (emphasis added); see also Sum-

nicht v. Toyota Motor Sales, U.S.A., Inc., 360 N.W.2d 2, 11 (Wis. 1984). This

standard requires a showing “that the conduct has such an effect in pro-

ducing the injury as to lead a reasonable person to regard it as a cause,

using that word in the popular sense.” Pieper v. Neuendorf Transp. Co., 274

N.W.2d 674, 677 (Wis. 1979); see also Murphy, 2022 WI 109, ¶ 19 n.14 (Wis.

2022).

We need not consider what impact, if any, this different standard may

have on plaintiffs’ appeal because neither party raised the issue in their

briefs, thereby waiving any argument related to the standard. Addition-

ally, any failure to cite the correct substantive state law is immaterial to

our decision because we find the district court acted within its discretion

to exclude Dr. Freeman’s causation opinion for lack of reliability under

federal procedural law.

12 No. 23-3162

Whether plaintiffs succeeded in making this showing

comes down to their causation expert Dr. Michael Freeman.3

Dr. Freeman, after reviewing questionnaire responses from

plaintiffs, concluded that the defective garments generally

and specifically caused plaintiffs’ injuries. The district court

ruled that Dr. Freeman’s report and testimony were inadmis-

sible under Federal Rule of Evidence 702, a decision plaintiffs

challenge on appeal. The ruling had significant consequences

since, as with the question of defect, plaintiffs needed expert

testimony to assist the jury in deciding whether Lands’ End

caused plaintiffs’ personal injuries. See City of Cedarburg Light

& Water Comm’n, 148 N.W.2d at 16–17.

Rule 702 requires parties to demonstrate that expert wit-

ness testimony is “based on sufficient facts or data” and “the

product of reliable principles and methods,” and that the ex-

pert “reliabl[y] appli[ed] … the principles and methods to the

facts of the case.” Fed. R. Evid. 702. District courts play an im-

portant gatekeeping function under Rule 702 and Daubert to

ensure that an expert’s testimony “is not only relevant, but

3 As Lands’ End points out, the December 2023 amendments to Rule

702 alter its reliability subsection to require that “the expert’s opinion re-

flect[] a reliable application of the principles and methods to the facts of

the case.” Fed. R. Evid. 702. This amendment was made to clarify that

“questions of the sufficiency of an expert’s basis[]” go to admissibility just

as with questions of “the application of the expert’s methodology.” Fed.

R. Evid. 702 advisory committee’s note to 2023 amendment. Lands’ End,

seeing this amendment as helpful to its case, advocates for its application

and suggests that it is in tension with this court’s precedent distinguishing

between reliable methodology and “the quality of an expert’s data and

conclusions.” Manpower, Inc. v. Ins. Co. of Pa., 732 F.3d 796, 806 (7th Cir.

2013). Because our conclusion is the same even under Manpower’s more

strict formulation of the standard, we will apply the pre-amendment Rule

just as the district court did.

No. 23-3162 13

reliable.” 509 U.S. at 589. District courts enjoy “substantial lat-

itude in making the findings necessary to fulfill this gatekeep-

ing role,” but “must provide more than just conclusory state-

ments of admissibility.” Von Duprin LLC v. Major Holdings,

LLC, 12 F.4th 751, 772 (7th Cir. 2021).

In the next sections, we consider whether the district court

abused its discretion in finding that Dr. Freeman unreliably

applied epidemiological principles when forming his causa-

tion opinion. We ultimately conclude the district court did not

abuse its discretion by finding that Dr. Freeman: (1) failed to

apply reliable epidemiological methods to a dataset; and (2)

did not reliably apply two epidemiological causation frame-

works.

a. Data Analysis

We begin with Dr. Freeman’s data analysis. To form his

causation opinion, Dr. Freeman relied exclusively on data col-

lected from questionnaires sent to nearly one thousand Delta

employees. 4 Lands’ End had prepared the questionnaire dur-

ing discovery in hopes of streamlining litigation. It asked re-

spondents to list what, if any, personal ailments they experi-

enced after wearing the new uniforms and the timing of their

symptoms.

The district court found the questionnaire was riddled

with design flaws that could produce biased results. For one,

only Delta employees who were already suing Lands’ End

and therefore had a financial interest in the outcome of the

4 Though the district court excluded Dr. Apple and Dr. Scheinman’s

causation opinions under Rule 702, plaintiffs only appeal the exclusion of

Dr. Freeman’s expert opinion. We therefore limit our analysis accordingly.

14 No. 23-3162

litigation received the questionnaires. Two, the question-

naires were created to streamline discovery, not to form the

basis of a multifaceted epidemiological study. Three, many

respondents gave erroneous or nonsensical responses, as Dr.

Freeman himself admitted at his deposition.

Dr. Freeman failed to recognize, let alone control for, any

of these shortcomings in his expert report. He only cursorily

acknowledged some of these issues during his deposition

when questioned by opposing counsel. This, to the district

court, constituted a failure to employ the routine methodol-

ogy of Dr. Freeman’s field, and it led the court to exclude his

causation opinions under Rule 702 and Daubert.

Plaintiffs argue that the district court improperly scruti-

nized their data’s quality rather than considering the reliabil-

ity of their expert’s methodology. We have indeed distin-

guished between Rule 702 challenges to the reliability of an

expert’s methodology and the reliability of an expert’s conclu-

sion. A district court is tasked under Rule 702 with “deter-

min[ing] that the expert used reliable methods,” but this obli-

gation “does not ordinarily extend to the reliability of the con-

clusions those methods produce—that is, whether the conclu-

sions are unimpeachable.” Stollings v. Ryobi Techs., Inc., 725

F.3d 753, 765 (7th Cir. 2013). District courts can “usurp[] the

role of the jury … if [they] unduly scrutinize[] the quality of

an expert’s data and conclusions rather than the reliability of

the methodology the expert employed.” Manpower, 732 F.3d

at 806. The line between data quality and methodological re-

liability “is not always an easy [one] to draw,” id., because

“conclusions and methodology are not entirely distinct from

one another,” Gen. Elec. Co. v. Joiner, 522 U.S. 136, 146 (1997).

No. 23-3162 15

But we encounter little difficulty here concluding that the

district court did not abuse its discretion in finding that Dr.

Freeman failed to employ the routine methodology of his

field.

As background, when faced with problems in their da-

tasets, epidemiologists “must identify potential biases and

analyze the amount or kind of error that might have been in-

duced by the bias.” Federal Judicial Center, Reference Manual

on Scientific Evidence 583 (3d ed.). Hence, epidemiologists in

the normal course would have produced an analysis that at

least acknowledged some of the data quality problems the

district court identified.

That is on full display in the Harvard Flight Attendant

Study Report that Dr. Freeman cites extensively in his report.

The study generally tracked the health outcomes of several

hundred flight attendants over several years. In the report,

epidemiologists compared the health outcomes of a group of

Alaska Airlines flight attendants who, like plaintiffs, alleged

their uniforms had made them sick against a control group.

Eileen McNeely et al., Symptoms Related to New Flight At-

tendant Uniforms, 927 BMC PUB. HEALTH 1 (2017). When com-

piling their research findings, the epidemiologists acknowl-

edged that the widespread complaints circulating among the

flight attendants regarding uniform-related adverse health

outcomes had the potential to increase symptom reporting

among their study participants. Id. at 5. The study authors

then noted that this bias risk was minimized by “the more

general purpose of the survey in which hundreds of data

points were gathered” about respondents’ health. Id.

Dr. Freeman did not attempt this minimal amount of

identifying or controlling for error. That goes to the heart of

16 No. 23-3162

the reliability of his methodology. Dr. Freeman’s professional

burden was clearly not an onerous one—we see from the

Harvard study that simply acknowledging potential

weaknesses in the data and considering a remedy may have

been sufficient. To satisfy Rule 702, Dr. Freeman did not have

to go to the lengths of collecting the questionnaire data

himself, reviewing plaintiffs’ medical records, or employing a

controlled study, though such measures would aid him on

cross-examination. Less was required but not done here.

Therefore, the district court did not abuse its discretion in

finding that Dr. Freeman failed to employ reliable data

analysis principles common to his field.

While we are able to affirm the district court’s decision to

grant summary judgment in Lands’ End’s favor on this

ground alone, we will discuss the remainder of plaintiffs’ cau-

sation arguments. We next consider whether Dr. Freeman re-

liably applied two epidemiological causation frameworks—

the Bradford-Hill criteria and Naranjo algorithm—for his cau-

sation opinions.

b. Bradford-Hill Criteria

To determine whether the garments could have caused

plaintiffs’ physical symptoms, Dr. Freeman used a “distilled”

three-step version of the Bradford-Hill analysis. The standard

Bradford-Hill analysis is a widely implemented nine-part ep-

idemiological framework used to determine whether a causal

relationship exists between a stimulus and symptomatic re-

sponse. See Reference Manual on Scientific Evidence 599–600; see

also In re Zoloft (Sertraline Hydrochloride) Prods. Liab. Litig., 858

F.3d 787, 795 (3d Cir. 2017) (finding the framework “generally

reliable”); Wendell v. GlaxoSmithKline LLC, 858 F.3d 1227, 1235

n.4 (9th Cir. 2017) (same).

No. 23-3162 17

Before conducting a Bradford-Hill analysis, an expert

must first conduct an associational analysis to determine

whether the stimulus and health response “occur together

more frequently than one would expect by chance.” Reference

Manual on Scientific Evidence 566. This is most often done by

comparing the health outcomes of those exposed to a toxic

substance with an unexposed control group. Id. at 218–19. Dr.

Freeman never engaged in this preliminary step before con-

ducting his distilled version of the Bradford-Hill analysis. The

district court found that this was a failure to reliably apply

clear epidemiological principles and was sufficient grounds

to exclude Dr. Freeman’s report.

Plaintiffs ask us to overlook Dr. Freeman’s oversight on

appeal. They argue that his passing reference to two instances

of alleged uniform-associated illness that struck Alaska Air-

lines and American Airlines flight attendants in 2011 and 2016

was a sufficient associational analysis. The district court rea-

sonably found this insufficient for two reasons.

First, and most importantly, there is no evidence that

Lands’ End manufactured or worked with the same garment

producers involved in making the flight attendant uniforms

for Alaska Airlines and American Airlines. Yet, Dr. Freeman

did not control for this variance as is necessary when compar-

ing association between multiple study groups. See Reference

Manual on Scientific Evidence 571.

Second, associational values normally are expressed as

numerical values calculated from one of several statistical for-

mulas. See id. at 566–71; see also McNeely, supra, at 6 (reporting

numerical association values). This is demonstrated in the

Harvard study. That study determined from Alaska Airlines

flight attendants’ self-reported health symptom data that

18 No. 23-3162

“flight attendant uniforms w[ere] associated with quantifia-

ble health effects.” See McNeely, supra, at 5–7. The study went

on to quantify the strength of those associations on a per-

symptom basis before undertaking its own causation analy-

sis. Id. Dr. Freeman’s report never similarly quantified the as-

sociation between garment exposure and any of plaintiffs’

personal injuries.

Beyond this preliminary step, Dr. Freeman’s report also

failed to reliably apply the Bradford-Hill criteria. The nine

Bradford-Hill variables are: (1) plausibility; (2) strength of

association; (3) consistency; (4) biological gradient (dose-

response relationship); (5) specificity of the association; (6)

analogy; (7) temporality; (8) experiment (cessation of

exposure); and (9) coherence. Austin Bradford-Hill, The

Environment and Disease: Association or Causation?, 58 PROC.

ROYAL SOC’Y MED. 295, 295–99 (1965). Instead of considering

these nine variables, Dr. Freeman employed a distilled test

that used three variables as stand-ins for the full Bradford-

Hill analysis. This tripartite analysis considered: “1) the

plausibility of the suspected causal relationship … ; 2) the

temporal aspects of the relationship … ; and 3) the likelihood

that an alternative cause other than the suspected cause

accounts for the observed relationship.”

The district court did not disqualify Dr. Freeman’s

analysis as unreliable merely because it lists fewer factors; we

will not either. The strict construction of a test is of less

concern so long as it faithfully applies reliable methodology.

See Etherton v. Owners Ins. Co., 829 F.3d 1209, 1218–23 (10th

Cir. 2016) (considering reliability of expert’s distilled

causation analysis). Nevertheless, we see no reason to undo

the district court’s conclusion that Dr. Freeman’s three-step

No. 23-3162 19

analysis falls short because it fails to sufficiently account for

the established Bradford-Hill criteria.

First, Dr. Freeman’s report does not discuss how the three

variables in his distilled analysis align with the nine in the

standard analysis. Dr. Freeman does not explain how plausi-

bility, temporality, and alternative causation alone account

for the other standard factors. And the academic articles that

Dr. Freeman relies on similarly fail to connect the dots be-

tween a distilled analysis and the standard framework.

Second, the articles Dr. Freeman cites apply distilled

Bradford-Hill analyses in epidemiological contexts rather

dissimilar from this case. Those studies applied a distilled

analysis in the study of vehicle crash trauma, arthritis,

fibromyalgia, and rotator-cuff injuries. Yet, Dr. Freeman does

not consider how those studies tend, or fail, to shed light on

the applicability of the truncated analysis to the toxic tort

arena.

Even still, plaintiffs argue that Dr. Freeman was not obli-

gated to consider each of the original nine Bradford-Hill fac-

tors because “there is no threshold number [of factors] that

must exist” to establish causation. Reference Manual on Scien-

tific Evidence 599–600. Though it is true that “[o]ne or more

factors may be absent even when a true causal relationship

exists,” this is only true where an expert has reliably applied

the Bradford-Hill analysis to begin with. Id. at 600. Plaintiffs’

argument that causation may be made out where only eight

of the nine variables are present does not bear on whether Dr.

Freeman reliably distilled the factors from nine down to three.

Therefore, we cannot say that the district court abused its dis-

cretion by highlighting Dr. Freeman’s failure to bridge the

20 No. 23-3162

analytical gap between the cited literature and the facts of this

case. See C.W., 807 F.3d at 836.

c. Naranjo Algorithm

Dr. Freeman also used another framework—the Naranjo

algorithm—to construct his general and specific causation

findings. The Naranjo algorithm is a test designed to deter-

mine whether a drug can cause a certain adverse reaction. The

algorithm consists of ten questions, the responses to which are

assigned a score. The questions ask, for example, whether

there were prior reports of similar adverse health reactions;

whether symptoms occurred following exposure and im-

proved with decreased exposure; whether alternative causa-

tions could explain the reaction; and if the toxins were de-

tected in blood or other bodily fluids. The sum of the individ-

ual scores then determines the strength of the causal relation-

ship, if one exists. Dr. Freeman modified the Naranjo algo-

rithm for his analysis and used many of the same findings and

data from his distilled Bradford-Hill analysis to find that the

garments generally and specifically caused plaintiffs’ injuries.

Lands’ End argued before the district court that the scien-

tific literature did not support the application of the Naranjo

algorithm outside of the adverse drug context, and that Dr.

Freeman inappropriately altered the analysis to favor plain-

tiffs’ preferred outcome. Plaintiffs argued in response that the

Naranjo algorithm is widely used, and that Dr. Freeman em-

ployed it as part of a totality-of-the-evidence analysis as laid

out in Milward v. Acuity Specialty Product Group, 639 F.3d 11,

17–18 (1st Cir. 2011). The district court did not acknowledge

or discuss Dr. Freeman’s general causation opinion based on

the Naranjo algorithm. The court did exclude his Naranjo al-

gorithm causation opinion on the grounds that Dr. Freeman

No. 23-3162 21

never undertook any of the six Milward steps involved in a

totality-of-the-evidence approach, and Dr. Freeman’s analysis

was plagued by the same uncritical use of the questionnaire

data we discussed earlier. See supra Part III.A.2.a.

Plaintiffs ask us to remand this case for the district court

to address whether Dr. Freeman reliably applied the Naranjo

algorithm in his alternative general causation analysis and in

his specific causation determination. While the district court

ought to have considered these issues in the first instance, re-

mand is unnecessary because plaintiffs have failed to carry

their burden as to the existence of a defect and as to causation

based on Dr. Freeman’s usage of the questionnaire data. See

O'Brien v. Caterpillar Inc., 900 F.3d 923, 928 (7th Cir. 2018) (we

may affirm summary judgment on any ground supported by

the record).

For these reasons, we affirm the district court’s exclusion

of the Andrews plaintiffs’ expert opinions on defect and cau-

sation and the ultimate grant of summary judgment in Lands’

End’s favor. That brings us to the Gilbert plaintiffs’ breach of

warranty claim.

B. Breach of Warranty

The Gilbert plaintiffs brought a breach of express war-

ranty claim under the contract that governed Delta’s purchase

of garments from Lands’ End—the Uniform Apparel Agree-

ment (“UAA”). Plaintiffs sought summary judgment as in-

tended beneficiaries under this contract, claiming that Lands’

End breached a provision of the UAA guaranteeing that “if at

any time, for any reason, … any actively employed Employee

is not 100% satisfied with their Products (even if they have

been washed, worn and/or embroidered), they can return

22 No. 23-3162

them at any time … for a refund or exchange.” The contract

mandated that “[a]ll returns and exchanges w[ould] be ac-

companied by a return/exchange form, as mutually agreed by

the parties.” Plaintiffs argue that Lands’ End breached this

provision by failing to issue refunds despite plaintiffs’ blanket

demand letter requesting them.

Lands’ End cross-moved for summary judgment on this

claim, arguing that they could not have breached the express

warranty provision given that plaintiffs failed to return their

garments as required under the UAA’s terms. The district

court sided with Lands’ End. The court noted that the unre-

futed evidentiary record showed that Lands’ End always is-

sued refunds or exchanges to Delta employees who returned

their garments and plaintiffs failed to submit any evidence es-

tablishing that Delta employees who returned their garments

were denied a refund.

On appeal, plaintiffs argue that the district court erred by

requiring plaintiffs’ strict compliance with the UAA’s require-

ment that plaintiffs return their uniform because the con-

tract’s terms were confidential, so plaintiffs could not have

complied. They also argue that the requirement runs afoul of

the Uniform Commercial Code’s bar on unreasonable re-

straints of express warranties. We conclude that summary

judgment in Lands’ End’s favor is appropriate.

Before addressing the merits, we must determine which

state’s substantive law to apply. The UAA had a choice of law

provision mandating the application of Delaware law. Be-

cause the district court had diversity subject-matter jurisdic-

tion, it was required to apply Wisconsin choice of law rules to

determine what law to apply. Tanner v. Juniper Realty Corp.,

433 F.3d 913, 915 (7th Cir. 2006). Wisconsin law honors choice

No. 23-3162 23

of law provisions in duly enacted contracts so long as doing

so would not run afoul of the state’s public policies. Drinkwa-

ter v. Am. Fam. Mut. Ins. Co., 2006 WI 56, ¶ 25. We agree with

the district court that no such policy concerns exist here, so,

like the district court, we will apply Delaware law and Dela-

ware’s version of the Uniform Commercial Code.

Under Delaware law, a beneficiary’s rights can be “ex-

pressly or impliedly limit[ed]” by the terms of an agreement.

Crispo v. Musk, 304 A.3d 567, 573 (Del. Ch. 2023). The same is

true of express warranty provisions so long as limitations on

the exercise of such warranties are reasonable. See 6 Del. C.

§ 2-316(1) (“Words or conduct relevant to the creation of an

express warranty and words or conduct tending to negate or

limit warranty shall be construed wherever reasonable as con-

sistent with each other.”). We have observed in other contexts

that this requirement “has been understood to forbid the com-

plete negation of an express warranty.” Bushendorf v. Freight-

liner Corp., 13 F.3d 1024, 1027 (7th Cir. 1993). After all, “a

clause in the same contract disclaiming [an express warranty]

… suggests some deep confusion which may warrant repara-

tive efforts by the court.” Id.

The UAA’s language easily passes muster under these

standards. The conditions precedent to a refund—that plain-

tiffs return their garments and fill out a form—are not so on-

erous that they completely negate the express warranty. Nei-

ther are the conditions unreasonable limitations on the war-

ranty.

Plaintiffs make much of the fact that they were not shown

the UAA’s terms. But it is common practice to condition a re-

fund on the return of the sold goods. That is borne out by the

fact that many Delta employees knew to return their uniforms

24 No. 23-3162

in exchange for a refund without being made aware of the

contract’s terms. Further, plaintiffs’ counsel certainly became

aware of the UAA’s terms during this litigation given that

they brought claims based on the contract’s terms in their op-

erative complaint. Yet, counsel appears to have failed to ad-

vise their clients to pursue this expedient route to relief de-

spite Lands’ End stating in its response to plaintiffs’ demand

letter that all plaintiffs would receive refunds upon return of

their garments.

For these reasons, summary judgment on this claim was

appropriate.

III

In sum, we affirm the grant of summary judgment to

Lands’ End on the Andrews plaintiffs’ personal injury claims.

None of plaintiffs’ experts offered testimony establishing that

the uniforms were defective, and the district court did not

abuse its discretion by excluding Dr. Freeman’s testimony af-

ter finding that he uncritically relied on faulty data in reach-

ing his causation opinions.

Summary judgment in Lands’ Ends favor on the Gilbert

plaintiffs’ breach of warranty claims was also appropriate be-

cause plaintiffs failed to abide by the warranty’s reasonable

terms. The judgment of the district court is AFFIRMED.