TWSA531A Audit Sampling 　 　 　

Status

Revised by Auditing Standards Committee in Taiwan on 4 October, 2022.

Summary

When designing audit procedures, the auditor should determine appropriate means for selecting items for testing so as to gather sufficient appropriate audit evidence to meet the objectives of the audit procedures.

Audit sampling involves the application of audit procedures to less than 100% of items within a class of transactions or account balance such that all sampling units have a chance of selection. This will enable the auditor to obtain and evaluate audit evidence about some characteristic of the items selected in order to form or assist in forming a conclusion concerning the population from which the sample is drawn. Audit sampling can use either a statistical or a non-statistical approach. 　

The auditor should apply professional judgment in designing audit sampling and take into account the following:

• The relationship of the sample to the relevant audit objective.
• Population and sampling units.
• Risks and confidence level.
• Tolerable deviations and misstatements.
• Expected deviations and misstatements in the population.
• Stratification.

Sampling risk arises from the possibility that the auditor’s conclusion, based on a sample, may be different from the conclusion he would reach if the entire population were subjected to the same audit procedure.

Sample items should be selected in such a way that the sample can be expected to be representative of the population. This requires that all items in the population have an opportunity of being selected.

While there are a number of selection methods, three methods commonly used are:

• Random selection,
• Systematic selection, and
• Haphazard selection.

Having carried out, on each sample item, those audit procedures that are appropriate to the particular audit objective, the auditor should:

• Analyze any deviations and misstatements detected in the sample.
• Project the deviations and misstatements found in the sample to the population, and
• Assess the sampling risk.

The auditor should project the deviations and misstatements results of the sample to the population from which the same was selected. When projecting deviations and misstatements results, the auditor should keep in mind the qualitative aspects of the deviations and misstatements found.

The auditor should project the deviations and misstatementserror results of the sample to the population from which the same was selected. When projecting deviations and misstatements error results, the auditor should keep in mind the qualitative aspects of the deviations and misstatementserrors found.

The auditor should consider whether deviations and misstatementserrors in the population might exceed the tolerable deviations and misstatementserror by comparing the projected population error to the tolerable deviations and misstatementserror and also then compare the sample result to the evidence obtained from other relevant audit procedures when forming his conclusions. 　

Effective date

This Standard is effective from 15 December, 2022.