What is the primary purpose of dual purpose samples in an audit?

The primary purpose of dual purpose samples in an audit is to evaluate both control and detail aspects. This approach allows auditors to gather sufficient evidence in a more efficient manner by using a single sample to meet different objectives.

When auditors use dual purpose sampling, they can simultaneously assess the effectiveness of internal controls (such as compliance with procedures and policies) while also obtaining substantive evidence about specific transactions or balances. For example, while reviewing sales transactions, an auditor can examine whether the sales process complies with established controls (like proper authorization) and also verify the accuracy of sales figures reported in the financial statements.

This method helps in maximizing the audit efficiency, as it effectively reduces the number of samples needed and therefore saves time while ensuring that both compliance and transaction accuracy are thoroughly evaluated. Such an approach is beneficial in creating a comprehensive understanding of the financial statements and the underlying processes that support them.