Abstract To ensure an effective and efficient engagement, audit planning of the nature, extent, and timing of procedures is crucial. This paper provides a review of the professional standards and research findings on evidential planning. The professional standards provide useful evidential concepts and advance several presumptions or "rules-of-thumb" to guide auditors. Early research findings, however, suggest that several widely used procedures may possess low error detection capabilities. Given the embryonic state of our knowledge on evidential quality, a "Contingency View" of evidence is outlined. In this view the cost-effectiveness of a source of evidence is dependent upon factors such as the nature of the client, the account, and the method of obtaining the evidence.
Wright et al. (Sun,) studied this question.