What is the test for reversal of a finding of full performance in a medical malpractice case?

Defendant insisted on reversal. The court said: 'Since a substantial performance is performance (Rowe v. Gerry, 112 App.Div. 358, 98 N.Y.S. 380), and all that is required to sustain an allegation of performance, and since the probative findings referred to show such performance, it follows that, instead of being inconsistent with the allegation of full performance, the findings to that effect are in full accord with and support the same.' (48 Cal.App. at page 458, 192 P. at page 140.)