AN ANALYSIS OF THE EFFECTS OF RISK, MATERIALITY AND STRUCTURE ON AUDITORS' EVIDENTIAL PLANNING DECISIONS

This research has developed a behavioral model that provided a more inclusive and realistic characterization of the evidential planning decisions of auditors than prior research. The model consists of five independent variables (inherent risk, control risk, desired audit risk, auditor business risk and planning materiality) and three moderating variables (audit structure, tolerance for ambiguity and auditor risk attitude). The model was tested using a field experiment approach. Seventy-nine experienced auditors from Big Six CPA firms in Hong Kong were requested to complete a questionnaire designed to measure those variables.; The research findings revealed that five independent variables were important factors in explaining auditors' planning decisions, and these had the following order of magnitude (from highest to lowest): control risk, inherent risk, auditor business risk, desired audit risk and planning materiality. In sum, they explained 37 percent of the variations in auditors' planned extent of audit evidence. These results lend support to the predictive ability of the proposed evidential planning model as well as the utilization of the conventional audit risk model by auditors in Hong Kong. In addition to considering audit risk and materiality, as required by the professional standards, this research has demonstrated that auditors implicitly do consider external business risk as a significant factor determining the extent (cost) of the audit to be conducted.; The findings revealed that auditors placed significantly less emphasis on the planning materiality variable, when compared to the audit risk components. A policy inference from this finding is that policy makers of CPA firms and/or the Hong Kong Society of Accountants should provide more explicit guidance and/or educational training to auditors about planning materiality if they desire that it be given more emphasis in the evidential planning decision.; The results also provided empirical evidence to support the moderating roles of the audit structure, tolerance for ambiguity and auditor risk attitude variables in auditors' planning decisions. Regarding the quality of auditor judgement, the indices for judgement consensus, stability and self-insight were found to be moderate, thus lending additional support to the proposed evidential planning model of auditors as a valid and stable model.