Final answer:
In audit procedures, appropriateness is about the relevance and reliability of audit evidence, while sufficiency concerns the amount of evidence. Both need careful consideration in terms of the sample size, selected items, and the timing of audit procedures, as they influence the accuracy and reliability of the audit conclusion.
Step-by-step explanation:
In the context of audit procedures, the concepts of appropriateness and sufficiency are interrelated and fundamental in obtaining sufficient, appropriate audit evidence. Appropriateness refers to the relevance and reliability of the evidence gathered during an audit, which means the audit procedures must be relevant to the assertions being tested and reliable in that the information is trustworthy and dependable. On the other hand, sufficiency pertains to the quantity of evidence obtained. It is the measure of the volume of evidence that an auditor collects; the more sufficient the evidence, the higher the likelihood that the auditor's conclusions are accurate.
Relating to sample size, items to select, and timing, both appropriateness and sufficiency must be considered. An auditor must choose a sample size that is sufficient to provide a basis for a reliable conclusion, but it must also be appropriate in that it is representative of the population as a whole and relevant to the specific risks being addressed. Similarly, the items selected for examination must be appropriate - relevant to the auditing objectives and reliable - while also being sufficient to support the auditor's opinion.
The timing of audit procedures can also impact both appropriateness and sufficiency. Performing audit procedures at an inappropriate time may result in evidence that is not relevant or reliable, while insufficient timing may lead to an inadequate gathering of evidence, which could affect the outcomes of the audit.