What is the test for credibility and weight of expert testimony in a personal injury case?

In any event, the determination of the credibility and weight to be given to the testimony of experts is made 'by the trier of fact and not by an appellate tribunal.' (Stern v. Krasne, 130 Cal.App.2d 818, 821, 280 P.2d 45, 47; see also Estate of Schmidt, 261 Cal.App.2d 262, 272, 67 Cal.Rptr. 847; Douglass v. Webb, 209 Cal.App.2d 290, 297, 26 Cal.Rptr. 60.)