What is the test for establishing identity of a defendant who has committed uncharged criminal acts similar to the charged offence?

Appellant argues that the prior bad acts must be "signature-like" but that is only where the evidence is offered to prove defendant's identity as the perpetrator. (People v. Ewoldt, supra, 7 Cal.4th at p. 403.) "[E]vidence that the defendant has committed uncharged criminal acts that are similar to the charged offense may be relevant if these acts demonstrate circumstantially that the defendant committed the charged offense pursuant to the same design or plan he or she used in committing the uncharged acts. Unlike evidence of uncharged acts used to prove identity, the plan need not be unusual or distinctive; it need only exist to support the inference that the defendant employed that plan in committing the charged offense. [Citation.]" (Id., at p. 403.) The least degree of similarity between the uncharged act and the charged offense is required to prove intent. (Id., at p. 402.)