What constitutes substantial evidence in a personal injury case?

"Where [a] statement of decision sets forth the factual and legal basis for the decision, any conflict in the evidence or reasonable inferences to be drawn from the facts will be resolved in support of the determination of the trial court decision." (In re Marriage of Hoffmeister (1987) 191 Cal.App.3d 351, 358.) "Substantial evidence includes circumstantial evidence and the reasonable inferences flowing therefrom." (Conservatorship of Walker (1989) 206 Cal.App.3d 1572, 1577.) "The testimony of a single credible witness may constitute substantial evidence." (City and County of San Francisco v. Ballard (2006) 136 Cal.App.4th 381, 396.)