What is the test for admitting evidence of misconduct in a criminal case?

Evidence Code section 1101, subdivision (a), provides that "evidence of a person's character or a trait of his or her character (whether in the form of an opinion, evidence of reputation, or evidence of specific instances of his or her conduct) is inadmissible when offered to prove his or her conduct on a specified occasion." (See also People v. Ewoldt (1994) 7 Cal.4th 380, 393.) However, "this rule does not prohibit admission of evidence of uncharged misconduct when such evidence is relevant to establish some fact other than the person's character or disposition." (Id. at p. 393.) Evidence Code section 1101, subdivision (b), permits "the admission of evidence that a person committed a crime, civil wrong, or other act when relevant to prove some fact (such as motive, opportunity, intent, preparation, plan, knowledge, identity, absence of mistake or accident . . . ) other than his or her disposition to commit such an act."