Vernon Dotson filed a claim for black lung benefits in February 1977. An administrative law judge (AU) ruled that Mr. Dotson was entitled to benefits, but the Benefits Review Board (the Board) reversed that decision, concluding that Peabody Coal had rebutted the presumption of pneumoconiosis. We reverse the decision of the Board and remand Mr. Dotson’s claim to the AU for rehearing.
I
Facts
Mr. Dotson worked in coal mine employment from 1933 to 1954 and from 1969 to 1977. He worked above ground in a preparation plant watching and repairing machinery, pushing buttons, and occasionally lifting heavy objects. After retiring in 1977, Mr. Dotson immediately filed for black lung benefits.
As is common in black lung cases that come before this court, Mr. Dotson’s record contains medical evidence both suggesting and negating pneumoconiosis. The evidence recommending pneumoconiosis includes a single reading of a chest x-ray taken in 1977, and a pulmonary function test (PFT) from November 1980 that produced sufficiently low values to invoke the interim presumption of pneumoconiosis un *1136 der 20 C.F.R. § 727.203(a)(2). 1 Dr. Roger Mitchell, whose qualifications are not in the record, reviewed the PFT, remeasured certain values, and concluded that the PFT was “acceptable.” Dr. Mitchell reviewed the tracings that accompanied the PFT and commented that “2 of three tracings look OK.” Dr. Mitchell offered no other interpretation of the PFT, nor did he assess Mr. Dotson’s physical condition.
Evidence offered by Peabody contradicting Mr. Dotson’s proof includes three negative readings of the 1977 chest x-ray and two uncontradicted negative readings of a 1979 chest x-ray. Dr. Joseph J. Renn, Dr. James V. Vest, and Dr. E.J. Morgan reviewed the November 1980 PFT and all three concluded that it was invalid for several reasons, most notably Mr. Dotson’s suboptimal effort and cooperation during the test. Two other physicians, Dr. Owen Taylor and Dr. Martin W. Davis, personally examined Mr. Dotson. In April 1977, Dr. Taylor diagnosed that Mr. Dotson suffered from “myocardial ischemia,” but he found no evidence of pneumoconiosis. Dr. Davis conducted a thorough examination of Mr. Dotson in February 1979 and concluded that there was no evidence of pneumoconio-sis nor of a permanent disability. He also found that Mr. Dotson was capable of performing his previous coal mine employment. Finally, Dr. Peter Tuteur reviewed Mr. Dotson’s entire medical file in October 1982. Included in Dr. Tuteur’s review was a deposition of Mr. Dotson taken in August 1982. Dr. Tuteur concluded that there was no evidence in the record to support a diagnosis of pneumoconiosis.
A formal hearing on Mr. Dotson’s case was held before AU Frederick Neusner on March 15,1983. On June 17,1983, the AU concluded that Mr. Dotson was entitled to benefits because Mr. Dotson had invoked the presumption of pneumoconiosis by virtue of the November 1980 PFT, and because Peabody had not rebutted that presumption. The AU found Dr. Mitchell’s 2 appraisal of the PFT more credible than the evaluations by Drs. Vest, Morgan and Renn. Among the reasons offered by the AU for disregarding the opinions of Drs. Vest, Morgan and Renn were: (1) Dr. Mitchell’s qualifications to analyze the PFT were as good as Drs. Vest’s Morgan’s and Renn’s; (2) the conclusions of Dr. Morgan and Dr. Vest had focused on the FVC reading of the PFT, and not on the more pertinent FEV reading; and (3) Dr. Renn had only concluded that several things were wrong with the PFT, but he had not alleged that the quality standards found in the regulations were not met. Accordingly, the AU determined that the results of the PFT should be accepted and Mr. Dotson was entitled to the presumption of pneumoconiosis.
With respect to Peabody’s attempt to rebut the interim presumption, the AU determined that the physical examinations conducted by Dr. Davis in 1979 and Dr. Taylor in 1977 were persuasive, and that the presumption of pneumoconiosis was rebutted for the time period until November 1980. However, the AU determined that Peabody had not offered any evidence to rebut the presumption triggered by the qualifying PFT score. The AU concluded that Peabody had offered no evidence to suggest that Mr. Dotson did not have pneu-moconiosis after November 1980 or that Mr. Dotson could do his usual coal mine work or comparable or gainful work after that date.
*1137 The Board reversed the judgment of the AU on the ground that Peabody had established rebuttal as a matter of law under 20 C.F.R. § 727.203(b)(2). 3 The Board noted that the AU had accepted as valid the medical opinions of Drs. Davis and Taylor that Mr. Dotson did not have pneumoconio-sis and that he could perform his usual coal mine work. The Board then said that the AU’s reason for rejecting that evidence for the post-1980 period was invalid. That is, the Board reasoned that the November 1980 qualifying PFT did not contradict the opinions of Drs. Davis and Taylor because the PFT was not probative of whether Mr. Dotson had pneumoconiosis or could perform coal mine work.
II
Discussion
Although this appeal comes to us from a decision of the Board, our task is to review the judgment of the ALJ.
Smith v. Director, OWCP,
A. Interim Presumption
Although it was not the basis for the Board’s decision to reverse the AU’s award of benefits, Peabody’s principal argument on appeal is that the AU irrationally allowed Mr. Dotson to invoke the interim presumption. In
Zeigler Coal Co. v. Sieberg,
Under
Mullins
and
Sieberg,
we must review the AU’s reasons for concluding that the PFT was valid to determine whether his decision was rational and supported by substantial evidence. In our view, the decision of the AU to credit the testimony of Dr. Mitchell over Drs. Renn, Vest and Morgan was irrational for at least three reasons. First, the AU determined
*1138
that Dr. Mitchell was as qualified as Drs. Renn, Vest and Morgan, even though Dr. Mitchell’s qualifications were not in the record. Although an AU is not bound by formal rules of evidence,
Consolidation Coal Co. v. Chubb,
Because of the errors in the AL.J's report, his decision to invoke the presumption was neither rational nor supported by substantial evidence. The ALT accepted a cursory analysis by Dr. Mitchell-"2 of three tracings look OK"-while disregarding the more thorough analyses of other physicians. Although it is manifestly the role of the AU to accept or reject medical testimony, the AU must do so for justifiable reasons, which did not happen here. We cannot say, however, based on the record before us, that Dotson's PFT was absolutely invalid. Thus, unless the Board correctly determined that Peabody was entitled to rebuttal as a matter of law, we must remand Mr. Dotson's claim to the AU for rehearing.
B. Rebuttal Analysis
The AU determined that Peabody had not rebutted the presumption of pneumoco-niosis because Peabody’s medical evidence was based on medical examinations that preceded the November 1980 PFT. Although the AU concluded that the previously obtained medical evidence was “documented and well-reasoned,” the AU dismissed that evidence simply because it antedated the PFT. The Board reversed the AU, adopting an equally rigid bright-line rule. Although the Board’s opinion was truncated, the Board essentially held that an uncontradicted, valid medical diagnosis rebuts a qualifying PFT as a matter of law.
In our view, the position of the AU and the Board both conflict with Department of Labor regulations. The AU’s result was unprincipled because he ignored the regulatory mandate to examine “all relevant medical evidence.” 20 C.F.R. § 727.203(b);
see also Mullins,
108 S.Ct. at
*1139
435-36. Nothing in the regulations suggests that rebuttal evidence that precedes a qualifying PFT must be disregarded. Indeed, the Department of Labor has expressly said that previously obtained evidence may be used to rebut an interim presumption. “[T]he Department cannot, as has been requested by some, look for the single item of evidence which would qualify a claimant on the basis of the interim presumption, and ignore other
previously obtained
evidence.” 43 Fed.Reg. 36826 (1978) (emphasis supplied) (quoted in
Mullins,
The position of the Board was equally flawed because it went to the opposite extreme. The Board concluded, as a matter of law, that Peabody had established rebuttal through the medical opinions of Dr. Taylor and Dr. Davis. Although a qualifying PFT says very little, if anything, about whether a coal mine employee can perform his usual work — nor does it constitute proof of pneumoconiosis,
Mullins,
In this case, the amount of time between the medical examinations and the PFT was not so substantial as to preclude rebuttal nor so insignificant as to compel it. The AU, and the Board, should have considered explicitly all relevant evidence, including Mr. Dotson’s deposition, the medical opinions of Dr. Taylor, Dr. Davis, and Dr. Peter Tuteur, and the amount of time between the medical examinations and the PFT, in determining whether Peabody had proved rebuttal. Although this case has already been around for too long, we have no alternative but to remand it to the AU; the decisions of the AU and of the Board were inappropriate. On remand, the AU should consider all relevant medical evidence, including any new evidence offered by either party, in determining Mr. Dotson’s entitlement to an interim presumption and Peabody’s right to rebuttal.
Reversed and Remanded
Notes
. This regulation allows a claimant to invoke a presumption of pneumoconiosis if he was engaged in coal mine employment for at least ten years and if:
Ventilatory studies establish the presence of a chronic respiratory or pulmonary disease ... as demonstrated by values which are equal to or less than the values specified in the following table:
Equal to or less than— FEV MW
67" or less.2.3 2
68" .2.4 96
69".2.4 96
70".2.5 100
71" .2.6 104
72" .2.6 104
73" or more.2.7 108
20 C.F.R. § 727.203(a)(2). Mr. Dotson’s purported FEV value was 2.0 and his MW was 80.
. The AU occasionally referred to Dr. Mitchell as "Dr. Sherman.”
. This regulation allows for rebuttal of a presumption when the employer establishes that "the individual is able to do his usual coal mine work or comparable and gainful work....” 20 C.F.R. § 727.203(b)(2).
. These standards provide general guidelines for the taking of PFTs. Among the requirements for a proper PFT are three tracings of the PFT, and a statement from the examiner regarding the individual's ability to understand directions and the degree to which the patient cooperated in taking the PFT.
. See supra note 4.
. The MW (Maximum Voluntary Ventilation) measures the maximum volume of air that can be moved by the patient’s respiratory apparatus in one minute. The FEV (Forced Expiratory Volume) measures the amount of air exhaled in one second on maximum effort.
See Underhill
v.
Peabody Coal Co.,
. The FVC (Forced Vital Capacity) requires the patient to take a deep breath and then blow air out as rapidly and forcibly as possible. The FEV is taken from the first second of the FVC.
