What is the test for determining whether there is sufficient cause for a preliminary hearing?

At a preliminary hearing, the magistrate must decide only whether there is "sufficient cause" to believe the defendant guilty of a probable offense. That phrase is generally equivalent to "reasonable and probable cause" which has been defined as such a state of facts as would lead a man of ordinary caution and prudence to believe and conscientiously entertain a strong suspicion of the guilt of the accused. (Penal Code 871, 872; People v. Uhlemann, 9 Cal.3d 662, 667, 511 P.2d 609, 108 Cal.Rptr. 657.)