The Director of the Office of Workers’ ,. tt n. j cu. * t> Compensation, United States Department of Labor (Director)) appealed from an award of b]ack lung benef¡ts to Geo rgia Congleton Respondent), a miner’s widow, The award wag made ¡nitially by an admin. istrative law judge (a.Lj.) and subsequently affírmed by the Benefitg Review Board (Board).
Thomas Congleton married the respondent in 1927. He died in January, 1967, at the age of 67. On October 15, 1971, respondent filed a claim for widow’s benefits *429under the Black Lung Benefits Act (the Act), 30 U.S.C. § 901 et seq. The claim was denied by the Social Security Administration in June, 1974, and the denial was affirmed by the Department of Labor in August, 1979.
On July 9, 1980, a formal hearing was held before an a.l.j. in London, Kentucky. Evidence adduced at the hearing included Social Security records documenting fifty-one quarters of coal mine employment by the deceased; a chronological work history prepared by respondent which purported to establish almost thirty years of coal mine work by her husband; numerous (and often conflicting) affidavits from former co-workers, relatives and friends of the deceased which stated that he had worked in coal mines most of his adult life and which also recorded the various affiants’ recollections of decedent’s breathing difficulties prior to his demise; testimony of the respondent and her daughter as to the longevity of the miner’s employment in numerous coal mines; medical records of Drs. Carl Cooper, Jr., and F.W. Hare, both of whom had treated the deceased during his lifetime; an X-ray taken April 14, 1964 which had been interpreted as showing “normal lung fields” by an unidentified reader; and the miner’s death certificate which listed myocardial infarction as the cause of death.
Based on the above evidence, the a.l.j. issued a decision and order awarding benefits in accordance with 30 U.S.C. § 921(c)(5), which provides a rebuttable presumption of entitlement to benefits for a widow whose husband had been engaged in coal mine employment for twenty-five years or more. The Board affirmed the a.l.j.’s decision on December 16, 1982, and the Director’s motion for reconsideration was denied by the Board on April 12, 1983. On appeal, the Director challenged the a.l. j.’s findings that (1) the respondent was entitled to the twenty-five year presumption, and (2) that the Director had failed to rebut the presumption.
The twenty-five year presumption applicable to the case at bar reads in pertinent part:
In the case of a miner who dies on or before March 1, 1978, and who was employed for twenty-five years or more in one or more coal mines before June 30, 1971, the eligible survivors of such miner shall be entitled to the payment of bene-fits____ unless it is established that at the time of his or her death such miner was not partially or totally disabled due to pneumoconiosis.
30 U.S.C. § 921(c)(5); § 411(c)(5) of the Act.
The a.l.j. found that the miner worked “well over twenty-five years” in the coal mines. This finding of fact can be upheld only if it is supported by substantial evidence. Haywood v. Secretary, 699 F.2d 277 (6th Cir.1983). However, it is critical to the appellate review process that the a.l.j. clearly set forth the rationale for his findings of fact and conclusions of law. Section 557(c)(3)(A) of the Administrative Procedures Act mandates that “... all decisions shall include a statement of — (A) findings and conclusions, and the reasons or basis therefore, on all the material issues of fact, law or discretion presented on the record ...” (emphasis added). The courts have respected this requirement by remanding cases where the reasoning for the a.l.j.’s conclusion is lacking and therefore presents inadequate information to accommodate a thorough review. See, e.g., Maxey v. Califano, 598 F.2d 874, 875, 876 (4th Cir.1979); Schaaf v. Mathews, 574 F.2d 157 (3rd Cir.1978); Arnold v. Secretary, 567 F.2d 258 (4th Cir.1977).
In the instant case, the a.l.j. merely credited the testimony of the respondent, her daughter, and the nine affidavits of former co-workers and friends as “unchallenged statements" which support his finding of twenty-five years of coal mine employment. However, the a.l.j. failed to provide his rationale for crediting this evidence. A more complete analysis by the a.l.j. is crucial in this case since the respondent’s testimony was uncertain as to the date when the decedent had terminated his coal mine employment — either in 1953 or 1958 — especially in light of the inconsistencies and wide disparities appearing in the various *430affidavits filed on claimant’s behalf attesting to the miner’s coal mine employment history during the periods of his lifetime.1 In addition, the a.l.j. completely ignored the Social Security earnings records which disclosed less than ten years of total coal mine employment between 1937 and 1953. (The Social Security records also reflect numerous periods of employment in non-coal mine related jobs, including work at Ford Motor Company, an ice company, International Harvester,2 a foundry and a shipyard.)
The dissent argues that “we ought not to be ‘disposed to overturn a sound decision if the agency’s path, although not ideally clear, may be reasonably discerned,’ ” slip op. at 12, (quoting Benmar Transport & Leasing Corp. v. ICC, 623 F.2d 740, 746 (2d Cir.1980)), and further asserts that “one can readily see that AU Egan was pursuaded by Mrs. Congleton’s evidence ...” Id. While the majority agrees with the dissent’s basic premises in this respect, we remain steadfast in our conviction that an a.l.j.’s conclusory opinion, which does not encompass a discussion of the evidence contrary to his findings, does not warrant affirmance. For even in applying the deferential standard of “substantial evidence,” the reviewing court must take into account the evidence of record that detracts from as well as supports the challenged findings of fact. See Universal Camera v. NLRB, 340 U.S. 474, 488, 71 S.Ct. 456, 464, 95 L.Ed. 456 (1951); Richardson v. Secretary, 735 F.2d 962, 964 (6th Cir.1984) (per cu-riam); Beavers v. Secretary, 577 F.2d 383, 387 (6th Cir.1978). In the instant case, the evidence presented was simply too vague and conflicting to support the decision in the form rendered by the a.l.j.
In sum, the a.l.j.’s failure to explain his reason for crediting certain testimony while ignoring more substantial evidence would normally necessitate a remand with directions for more specific findings of fact. However, remand is not required in this case.
As mentioned previously, the Director’s second argument was that even if the presumption was properly raised, it was effectively rebutted as a matter of law. Rebuttal is accomplished when the Director has shown either the absence of reduced work ability or the absence of the disease at the time of death. See 20 C.F.R. §§ 727.204(c) and (d).
The medical evidence in the instant case unequivocally established that the deceased miner was not suffering from the disease at the time of his death. The medical records of the decedent’s treating physicians, Drs. Cooper and Hare, detailed a long history of serious heart disease, but *431were completely devoid of any reference even inferring any chronic lung impairment. To the contrary, during one examination (date unknown), Dr. Hare noted that the miner’s “lungs were clear as to auscultation and percussion.” In addition, the miner’s death certificate listed only myocardial infarction as the cause of death. While the death certificate by itself would not be sufficient to rebut the presumption, see 20 C.F.R. § 727.204(d)(4), the certificate, when paired with the extensive medical records of the miner’s own treating physicians which contain absolutely no indication that the miner was suffering from pneumoconiosis, constitute sufficient grounds for rebuttal.3
It must be emphasized that the above holding is not, as the dissent poses, the result of an impermissible shifting of the burden of proof from the Director to the claimant. The court is fully cognizant that the burden remains squarely on the Director to establish that the deceased minor did not suffer from pneumoconiosis at the time of his demise in order to effectuate rebuttal. Today’s decision merely enunciates the simple and elementary premise that when the Director effectively proves an absolute absence of chronic lung disease in any of the medical records available regarding the deceased, especially where, as here, the miner’s own physicians closely monitored his health for a number of years before his death, the Director has rebutted the presumption of disability due to pneumoconiosis as a matter of law.
To hold otherwise would, in effect, permit an irrebuttable presumption in favor of the claimant. Despite the liberal construction normally accorded the Black Lung Act, this court cannot, by judicial decree, legislate the conclusion suggested by the dissent. If the presumption has not been rebutted by the facts of the instant case, then this court is at a loss to conceive any situation in which the Director could prevail.
In sum, the a.l.j. erred in not setting forth, in definitive language, his assessment of the relative credibility of the evidence which led to his conclusion that the claimant’s decedent had worked in the coal mines for twenty-five years or more. But even assuming, arguendo, that the respondent had established entitlement to the twenty-five year presumption said presumption, was rebutted.
The decision of the Board and the a.l.j. is reversed and the award of benefits vacated.
. The affidavits are, for the most part, nonspecific or contradictory as to dates of employment and names of coal companies for which the deceased purportedly worked. For example, one Edward Gregory averred that the deceased worked "20 years or more" in the coal mines, but also listed dates which conflicted with the deceased’s non-coal mine employment as established by Social Security records. Another affi-ant, one William Gregory, stated that he knew the miner for 45 years and that the deceased "worked in the coal mines for the entire number of years that I knew him”. Again, this statement conflicted with Congleton’s non-mine employment. Even the deceased’s first cousin, Thomas Jefferson Congleton, a former coal company owner and manager, acknowledged that "there are no longer any pay records available" regarding the deceased's tenure with that company and that “it is too long to remember specifically” what dates decedent worked. None of these inconsistencies or admitted memory failures were addressed by the a.l.j.
. The dissent alleges that the majority "erroneously characterizes” Congleton’s employment by International Harvester as non-coal mine related because his widow testified that he worked as a coal miner for that company in Benham, Kentucky. Slip op. at 13. However, the dissent overlooks the fact that the “Chronological Work History" prepared by the miner's widow is void of any reference to coal-related work with International Harvester, although it does list coal employment in Benham, Kentucky with Bethlehem Steel in 1940. To further complicate the issue, Social Security records reflect that the decedent was employed with International Harvester in Columbus, Ohio during 1940 and 1941, and with the Bethlehem/Fairfield Shipyard in Bethlehem, Pennsylvania in 1942 and 1943. In sum, these discrepancies are illustrative of the conflicts in evidence which the a.l.j. failed to reconcile.
. Although the negative X-ray report submitted into evidence was also indicative of the absence of pneumoconiosis, it did not bear the name or qualifications of the technician who took the film nor the physician who interpreted it, and therefore does not meet the requirements for the admission of X-ray evidence as found in 20 C.F.R. § 718.102(c). As a result, the X-ray has no evidentiary value and cannot be considered by this court, as 20 C.F.R. § 718.102(e) states that "[n]o chest X-ray shall constitute evidence of the presence or absence of pneumoconiosis unless it is in substantial compliance with the requirements of this section ...”