Here you go, straight from the professional literature, AU 318 .33
“When responding to the risk assessment, the auditor may design a test of controls to be performed concurrently with a test of details on the same transaction. The objective of tests of controls is to evaluate whether a control operated effectively.”
“The objective of tests of details is to support relevant assertions or detect material misstatements at the relevant assertion level. Although these objectives are different, both may be accomplished concurrently through performance of a test of controls and a test of details on the same transaction, known as a dual-purpose test. For example, the auditor may examine an invoice to determine whether it has been approved and to provide substantive evidence of a transaction. The auditor should carefully consider the design and evaluation of such tests in order to accomplish both objectives. Furthermore, when performing such tests the auditor should consider how the outcome of the tests of controls may affect the auditor’s determination about the extent of substantive procedures to be performed. For example, if controls are found to be ineffective, the auditor should consider whether the sample size for substantive procedures should be increased from that originally planned.”
FAR - 89 (8/19/14) Wiley TB, Wiley Book, Books from School, Ninja Audio/Notes
AUD - 92 (10/14/14) Wiley TB, Wiley Book, Ninja Audio
BEC - 82 (5/8/15) Mostly Ninja MCQ, sprinkles of Becker lectures and Ninja Audio
REG - (8/14/15)
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