What is the legal test for disclosing confidential records to the defense?

Under the procedure set forth in Penal Code section 1326, when, as here, a criminal defendant has subpoenaed confidential records of a nonparty, the court may order an in camera hearing to determine whether or not the defense is entitled to receive the documents. (Id., 1326, subd. (c).) Upon request, an appellate court's role is to review the confidential records that were not disclosed by the trial court to determine whether they were material and should have been disclosed. (People v. Martinez (2009) 47 Cal.4th 399, 453.) [E]vidence is material only if there is a reasonable probability that, had the evidence been disclosed to the defense, the result of the proceeding would have been different. A reasonable probability' is a probability sufficient to undermine confidence in the outcome.' [Citations.] We also consider the effect of nondisclosure on the investigations conducted by counsel and on counsel's trial strategy. (Id. at pp. 453-454.)