"In an application for review of an award on the ground of change in condition, the burden is on the party alleging such change to prove his allegations by a preponderance of the evidence." Pilot Freight Carriers, Inc. v. Reeves, 1 Va. App. 435, 438-39, 339 S.E.2d 570, 572 (1986). On appeal, we view the evidence in the light most favorable to Nichols, the prevailing party. See R.G. Moore Bldg. Corp. v. Mullins, 10 Va. App. 211, 212, 390 S.E.2d 788, 788 (1990). We accept the commission's factual findings when they are supported by credible evidence. See James v. Capitol Steel Constr. Co., 8 Va. App. 512, 515, 382 S.E.2d 487, 488 (1989).