dissenting: It is undisputed the burden of proof is on the claimant to show the injury is compensable. The Workers Compensation Board, in reversing the ALJ’s award, concluded that Nance failed to carry this burden, stating:
“The only medical evidence dealing with claimant’s increased symptomatology comes from Dr. Anthony Pollock. Dr. Pollock, a board-certified orthopedic surgeon, had the opportunity to examine and treat claimant for both the 1990 injury and for the 1994 condition. While he noted the MRIs performed on claimant on October, 1994 showed a definite increase in the disc herniation at L5-S1, Dr. Pollock had significant difficulty attributing this progressive condition to claimant’s 1990 injuiy. He was asked specifically the cause of this increased condition and testified at various places in the transcript that the condition was caused by progressive degenerative disc disease, or possibly from the natural aging process; in another place he testified that he did not know what the cause was but he felt it may be the natural aging process; and finally he testified that he was not sure if it was caused by the injury or the natural aging process. The Appeals Board finds Dr. Pollock cannot relate claimant’s worsening condition to the 1990 work-related injury.”
In Syl. ¶ 7, the majority states, “A negative finding of fact will not be disturbed on appeal absent an arbitrary disregard of undisputed evidence or some extrinsic consideration such as bias, passion, or prejudice.” This is the standard under which we review the evidence in this case.
Under this standard of review, the record supports the Board’s findings, even as that record is summarized by the majority. Dr. Pollock testified that the worsening condition of Nance’s back could have been the result of the natural aging process. He was uncertain, even with the MRI, whether the primary injury was the cause of the changes in Nance’s back. The Board retied on this evidence in reaching its conclusion that claimant had not met his burden of proof relating his present condition to the prior injury.
From this same evidence, the majority reaches the “inevitable” conclusion that the deterioration of Nance’s back injury was a “direct and natural consequence of the first injury.” This is a distortion of Dr. Pollock’s testimony and of the majority’s own narration of that testimony. This “inevitable” conclusion was controverted by the only medical expert testifying on causation, Dr. Pollock. The majority then states: “There is simply no conclusion to be drawn *556from Dr. Pollock’s testimony but that the deterioration of Nance’s back is the result of the earlier compensable injury.” It is unlikely even Dr. Pollock would agree with drat characterization of his testimony. Dr. Pollock’s testimony that the deterioration could have been from the natural aging process was the testimony upon which the Board based its findings that claimant has failed to carry his burden of proof. Thus, the evidence on causation was not “undisputed evidence.” Under such circumstances, there can be no “arbitrary disregard of undisputed evidence.” With the limited scope of appellate review accorded negative findings, an appellate court is precluded from disturbing the Board’s findings on the record herein.
In reaching the conclusion that it does here, the majority alters the burden of proof by, in essence, requiring respondent to prove some intervening cause is responsible for the changed condition. Further, a reviewing court is not at liberty to reweigh the evidence, as I believe the Court of Appeals did and as the majority herein is approving.
I would reverse the judgment of the Court of Appeals and affirm the decision of the Board.
Six, J., joins the foregoing dissent.