Test of controls

A test of controls evaluates whether a control operated effectively in preventing, or detecting and correcting, material misstatements at the assertion level. The auditor determines which control to test and the period covered, then inspects evidence, observes, inquires or reperforms as appropriate. Tests may be necessary when the auditor plans to rely on a control or when substantive procedures alone cannot provide sufficient appropriate evidence. The auditor considers the control’s frequency, who performed it, deviations and whether evidence covers the period of intended reliance.