The best way to ensure the integrity of requirements is to:

Version control is a technique that helps to manage changes to requirements and ensure that only authorized changes are made. It also helps to maintain a history of requirements changes, which records the date, reason, and impact of each change. Tracking the status of each requirement helps to monitor the progress and completion of requirements throughout the project life cycle. These practices help to ensure the integrity of requirements and avoid confusion, inconsistency, or ambiguity. References: = PMI Professional in Business Analysis (PMI-PBA)® Examination Content Outline (2019), page 8; Business Analysis for Practitioners: A Practice Guide (2015), page 38.