An audit trail is a chronological, secure, computer-generated electronic record that makes it possible to reconstruct the sequence of events related to the creation, modification, or deletion of an electronic record. In clinical research, an audit trail is a fundamental feature of validated computerized systems (such as EDC or eTMF systems) that comply with the requirements of 21 CFR Part 11.
The audit trail provides a complete record of who made which change, when it was made (with date and time stamp), and what the original and new values were. This function is essential to ensure data integrity in accordance with the ALCOA+ principles. For CROs and sponsors, audit trails are a critical tool for demonstrating the validity of study data during regulatory inspections. They provide a transparent, traceable history of all data changes and are therefore a cornerstone of the credibility of study results.