The opinion
FRIEDMAN, Judge.
USAir, Inc. and its workmen’s compensation insurance carrier, American Motorists Insurance Company, appeal an order *102 of the Workmen’s Compensation Appeal Board (Board) which reversed a referee’s order denying benefits to Gail Schwarz. We vacate and remand.
Schwarz has been employed by USAir as a flight attendant since the early 1970’s. While on duty, she was required to wear high heels and be on her feet a large portion of the time.. After working for USAir for several years, she began to experience pain in her feet. She went to various health providers for treatment of her feet, submitting the costs of that treatment of USAir’s group health insurance plan. Eventually, the pain became so severe that Schwarz had surgery performed on both of her feet oh October 16, 1989. On October 25, 1989, she informed USAir that the surgery was for a work related condition. Schwarz returned to work on January 1, 1990.
In March of 1990, Schwarz filed a claim petition, alleging that she was disabled for the period from October 16, 1989 until her return to work, as the result of a work related injury. Schwarz testified and described her work duties. Because her claim was for less than twenty-five weeks of compensation, Schwarz introduced a report of Dr. Steven J. Hutton, the surgeon who operated on her feet. 1 Dr. Hutton described Schwarz’ problem as bilateral intermetatarsal neuromas (chronically inflamed nerves), which he excised during the surgery. Dr. Hutton also stated that “[t]he condition was possibly caused and certainly aggravated by prolonged standing and walking on hard surfaces in pump styled shoes all of which are required in her job as a flight attendant.” (Letter of Dr. Hutton, 10/24/89.)
*103 The referee issued a decision and order on May 23, 1991, and therein made the following finding of fact:
9. Having reviewed the medical [testimony] supplied by the claimant and the claimant’s testimony, it is this Referee’s opinion that the claimant was well aware of her foot-related problems considerably before 120 days prior to her notice to the defendant on October 25, 1989 and, in fact, the claimant testifies that the time was closer to ten years prior to the date of the operation that she was aware she was having problems with her feet.
(Referee’s decision and order, 5/23/91.) Based upon this factual finding, the referee dismissed the claim petition, concluding that because Schwarz was first injured some ten years earlier, she had failed to give timely notice as required by section 311 of the Act, 77 P.S. 631, which provides in pertinent part that “unless such notice [of the injury] be given [to the employer] within one hundred and twenty days after the occurrence of the injury, no compensation shall be allowed.... ”
Schwarz appealed to the Board. By an order of September 4, 1992, the Board reversed and awarded Schwarz compensation from October 16, 1989 to January 1, 1990. The Board based its order on the conclusion that Schwarz was required to give the notice required by section 311 within 120 days .of her loss of earning power. USAir now seeks our review. 2
USAir first argues that the Board erred when it relied upon Jones & Laughlin Steel Corp. v. Workmen’s Compensation Appeal Board (Glemzua), 35 Pa.Commonwealth Ct. 610, 387 A.2d 174 (1978) to support its conclusion that the notice required by section 311 began to run from the date that Schwarz actually became disabled; i.e., the date she lost earning power. We agree. The claimant in Jones & Laugh *104 lin, unlike Schwarz, suffered from an occupational disease as set forth in section 108(k) of The Pennsylvania Occupational Disease Act 3 . Section 311 specifically provided then, as it does today, that, in cases of occupational disease, an “injury” occurs when the claimant becomes disabled from that disease. 77 P.S. § 631 4 . Schwarz admits that she did not attempt to prove that she suffered from an occupational disease; therefore, the Board erred in concluding that Schwarz’ injury began when she was no longer able to work.
USAir next argues that the Board erred in concluding that Schwarz gave timely notice under section 311. As we have discussed, resolution of this dispute centers on when Schwarz was “injured” within the meaning of this section. USAir contends that the referee correctly determined that Schwarz’ date of “injury” preceded her petition by over ten years.
In support of this argument, USAir refers to the following testimony by Schwarz on direct examination:
Q When did you first start experiencing pain with your feet?
A Oh, about fifteen years ago, I would say.
Q And did you seek any kind of treatment for that?
A Yes, within, oh probably the last ten years. The pain got so severe, I started to go to a podiatrist.
Q In (sic) what affect did your job have on your feet?
A Well, it just made — when I went to work, when I had to wear heels, when I had. to stand for prolonged periods of time, it caused excruciating pain, and I had to keep going to the doctor for some kind of treatment.
*105 Q When you were off the job, was that pain alleviated at all?
A Oh, yes. I wasn’t wearing heels. I was wearing Reeboks or something to cushion my feet.
Q Reeboks are what?
A Tennis shoes.
Q So when you weren’t wearing high heels as part of your uniform, the pain was alleviated?
A A lot of it, most of it, yes.
(Notes of Testimony, 5/1/90, pp. 6-7.) On cross examination, the following occurred:
Q What seemed to aggravate the condition? Anything to you seem to aggravate the condition?
A Yes, heels, standing long periods of time in heels.
Q So you were suffering from this condition for at least ten years?
A Well, more than ten years. I would say 15, but before I went to the doctor, it was a while before I went to the doctor.
Q And in your opinion, it was the job that was causing and aggravating the condition?
A Yes.
(Id., pp. 11-12.)
Given this testimony, USAir argues that the present case is controlled by Bolitch v. Workmen’s Compensation Appeal Board (Volkswagen of America, Inc.), 132 Pa.Commonwealth Ct. 110, 572 A.2d 39 , petition for allowance of appeal denied, 526 Pa. 639 , 584 A.2d 321 (1990). In Bolitch , the claimant testified that she began experiencing back pain while at work on May 1, 1986. She continued to work and was on vacation for the month of July, 1986. When she returned to work in August 1986, the pain returned. She saw an orthopedic surgeon on September 9, 1986, who told the claimant that she had a ruptured disc. On September 11, 1986, after working for three hours, the claimant informed her employer of the work injury and left work. The referee specifically found that *106 the claimant injured her back on May 1, 1986 and knew then that the injury was work related. The referee specifically rejected her testimony that she suffered either a new injury or an aggravation of the May 1 injury on September 11. The referee noted that the claimant’s medical expert never offered an opinion as to when the disc actually ruptured. Thus, the referee dismissed the claim petition, concluding that the notice given by the claimant on September 11, 1986 was more than 120 days after her injury occurred on May 1, 1986 and so was untimely under section 311.
On appeal to this court, the claimant argued that the referee had erred in dismissing her claim petition, asserting, inter alia, that the referee’s finding that she knew the May 1 injury was work related 5 was not supported by substantial evidence. We reviewed the claimant’s own testimony and concluded:
A fair reading of the claimant’s testimony establishes that claimant’s back pain began at work on May 1,1986, that the back pain continued for some period of time and that her work increased her pain. Under these facts, it is fairly obvious that the claimant should have known as of the date of her injury that her injury was work related. Consequently, we believe there is substantial evidence to support the referee’s finding that the claimant knew of the' nature of her injury and that it was work related on May 1, 1986.
Bolitch , 132 Pa.Commonwealth Ct. at 116, 572 A.2d at 43 .
We concede that Schwarz’ testimony, like that of the claimant in Bolitch , supports the referee’s factual finding that Schwarz was aware that she was suffering from a work related injury for nearly ten years. This conclusion, however, does not end our inquiry.
Schwarz argues that her medical evidence proves that she essentially suffered a “new injury” each day that she went to work, relying on the medical report of her surgeon which clearly stated that Schwarz’ condition “was ... certainly ag *107 gravated” by her daily work duties. Schwarz’ theory in this regard certainly is supported by precedent of this court.
In Mancini’s Bakery v. Workmen’s Compensation Appeal Board (Leone), 155 Pa. Commonwealth Ct. 641 , 625 A.2d 1308 (1992), the claimant had a preexisting knee problem which his doctor diagnosed as being aggravated by his work. In 1983, the claimant had arthroscopic surgery and thereafter continued to work despite his problems. He began to experience knee pain again in 1987; in 1988, he consulted with another doctor who confirmed that the claimant was suffering from the same preexisting knee problem. The doctor recommended surgery. Within a month, the claimant filed a claim petition. At the hearing, the medical experts testified that the claimant’s work duties constantly aggravated the preexisting condition. The referee found the medical evidence to be credible and awarded benefits. On appeal, the employer contended that the claimant had failed to give timely notice under section 311 and had failed to file his claim petition within three years of the “injury” as required by section 315 of the Act. 77 P.S. § 602. The employer argued, as does USAir in the present case, that the claimant was aware of the “injury” when the original diagnosis was made in 1982. We rejected this argument, stating:
The medical evidence presented by both parties clearly established, and the referee found, that Claimant was suffering from a preexisting condition aggravated by the requirements of his job. Each day that Claimant worked constituted a ‘new’ injury in that it further aggravated his condition. See Eddy [v. Workmen’s Compensation Appeal Board (Bell Transit Inc.), 130 Pa.Commonwealth Ct. 306, 568 A.2d 279 (1989), petition for allowance of appeal granted, 525 Pa. 606 , 575 A.2d 570 (1990) ]; McDevitt v. Workmen’s Compensation Appeal Board (Ron Davidson Chevrolet), 106 Pa.Commonwealth Ct. 207, 525 A.2d 1252 (1987), petition for allowance of appeal granted, 518 Pa. 629 , 541 A.2d 1140 (1988), appeal dismissed as improvidently granted, 520 Pa. 119 , 552 A.2d 1048 (1989); Young v. Workmen’s Compensation Appeal Board (Jones & Laughlin Steel *108 Corp.), 97 Pa.Commonwealth Ct. 356, 509 A.2d 945 (1986); Divine Providence Hospital v. Workmen’s Compensation Appeal Board (Bonner), 75 Pa.Commonwealth Ct. 565, 462 A.2d 917 (1983); Beaver Supermarket v. Workmen’s Compensation Appeal Board, 56 Pa.Commonwealth Ct. 505, 424 A.2d 1023 (1981).
Mancini’s Bakery , 155 Pa.Commonwealth Ct. at 645-646, 625 A.2d at 1311 . Thus, in Mancini’s, we reasoned that because the claimant continued to work, thereby suffering daily aggravation of his condition, the last injury occurred on the last day of work and the requirements of both section 311 and section 315 were met.
In the present case, the referee failed to make findings of fact on the credibility of the medical evidence of Dr. Hutton that the claimant’s condition was aggravated each day on the job. Rather, the referee merely restated the opinion of Dr. Hutton without passing on his credibility. Accordingly, a remand is necessary to permit the referee to perform his function as factfinder. 6
Vacated and remanded. 7
*109 ORDER
AND NOW, this 23rd day of November, 1993, the September 4, 1992 order of the Workmen’s Compensation Appeal Board at No. A-91-1229 is vacated and the matter is remanded to permit the referee to make a credibility determination on the medical evidence of Dr. Steven Hutton.
Jurisdiction relinquished.
. Section 422 of The Pennsylvania Workmen’s Compensation Act, Act of June 2, 1915, P.L. 736, as amended, 77 P.S. § 835, provides:
Where any claim for compensation at issue before a referee involves twenty-five weeks or less of disability, either the employe or the employer may submit a certificate by any qualified physician as the history, examination, treatment, diagnosis and cause of the condition ... and such statements shall be admissible as evidence of medical and surgical ... matters therein stated and findings of fact may be based upon such certificates or such reports.
. Because only Schwarz, the party with the burden of proof, presented evidence yet failed to prevail before the factfinder, the scope of review in this case is limited to determining if a constitutional violation occurred or an error of law was committed and ascertaining if the referee capriciously disregarded competent evidence. McGarry v. Workmen’s Compensation Appeal Board (Morrissey). 146 Pa.Commonwealth Ct. 594, 606 A.2d 648 (1992).
. Act of June 21, 1939, P.L. 566, as amended, 77 P.S. § 1208(k).
. "In cases involving other that occupational diseases, [the 120 day period of section 311] begins to run when the injured employee knows, or reasonably should know, of the nature of his injury and its relationship to employment, regardless of whether the injured employee is disabled by the injury.” Leber v. Workmen’s Compensation Appeal Board (Yellow Freight System), 156 Pa.Commonwealth Ct. 491, 495, 628 A.2d 481, 484 (1993) (emphasis added).
. We held that the 120 period in section 311 does not begin to run until an injured worker knows or should have known that an injury is work related. E.J.T. Construction, Inc. v. Workmen's Compensation Appeal Board (Larusso), 47 Pa.Commonwealth Ct. 492, 408 A.2d 226 (1979).
. While we are permitted to affirm an order of an administrative tribunal whose reasoning was erroneous if the correct reasons are apparent from the face of the record, Gregorious v. Workmen’s Compensation Appeal Board (European Health Spas), 87 Pa.Commonwealth Ct. 86, 486 A.2d 564 (1985), this principle is inapplicable to the present case because of the necessity of credibility findings.
. We must note that our recent case of Brooks v. Workmen’s Compensation Appeal Board (Anchor Glass Container), 155 Pa.Commonwealth Ct. 248, 624 A.2d 821 (1993) is distinguishable. In that case, the claimant was diagnosed as suffering from work related carpal tunnel syndrome in May of 1985. The claimant continued to work until the pain prevented him from doing so. He filed a claim petition in June of 1989, over four years after being made aware of the work related injury. We held that the claim petition was untimely under section 315. In that case, however, “the [medical] testimony indicated, and the referee found, that the cumulative effect of work-related circumstances on [claimant actually resulted in carpal tunnel syndrome, the injury, in 1985.” Brooks , 155 Pa.Commonwealth Ct. at 252, 624 A.2d at 823 . The claimant in Broolcs, unlike either the claimant in Mancini's or Schwarz, presented no medical evidence to the effect that by performing daily work duties, claimant suffered a new injury each day on the job.