Certified Information Systems Auditor Practice Exam 2025 – All-in-One Guide to Master Your CISA Certification!

Preparing simulated transactions is the most effective method for confirming the accuracy of system tax calculations because it allows for real-time testing of the system's functionality in processing tax calculations. By creating a variety of hypothetical transactions resembling actual business activities, auditors can verify whether the system accurately calculates the tax amounts based on current rules and regulations. Simulated transactions can help identify discrepancies between expected and actual results, which is crucial for determining the reliability of the system's tax calculation processes.

While reviewing past tax filings can provide insights into previous performance and trends, it does not directly validate the accuracy of current system calculations. Conducting interviews with accountants may provide qualitative insights into the system's usage and features, but it does not furnish concrete evidence of accuracy in calculations. Analyzing changes in tax laws is important for ensuring compliance, but it does not confirm the effectiveness of the system in implementing those changes.

Using simulated transactions establishes a hands-on approach to testing that can uncover potential issues and enhance confidence in the system's accuracy.