Which method is best for an IS auditor to detect duplicate invoice records?

The most effective method for an IS auditor to detect duplicate invoice records is through the use of computer-assisted audit techniques (CAATs). These techniques leverage automated tools and software to analyze large volumes of data efficiently and accurately, enabling the auditor to identify patterns and anomalies, such as duplicate records, that may not be easily detectable through manual review.

CAATs can perform tasks like data matching and extraction, which are specifically useful for identifying duplicates by scanning for identical values in critical fields, such as invoice numbers, amounts, and dates. The ability to process and analyze extensive datasets quickly makes computer-assisted techniques particularly advantageous in modern audits, where the volume and complexity of financial data can be substantial.

Other methods, like attribute sampling, are more suited for assessing specific characteristics of data rather than identifying duplicates. Compliance testing focuses on checking adherence to policies and procedures, which does not directly address the identification of duplicate records. Integrated test facilities are primarily used to test systems in live operating environments but do not directly facilitate the detection of duplicates in historical data records. Thus, computer-assisted audit techniques stand out as the optimal choice for effectively uncovering duplicate invoices.