[The following paragraph was effective before December 31, 2016. See PCAOB Release No. 2015-002. The current standard can be found here.]
The practitioner should apply procedures to provide reasonable assurance of detecting material noncompliance. Determining these procedures and evaluating the sufficiency of the evidence obtained are matters of professional judgment. When exercising such judgment, practitioners should consider the guidance contained in section 101.51-.54 and AU section 350, Audit Sampling.