The audit trail provides the documentary evidence that enables reconstruction of the sequence of events related to clinical trial data, serving as a fundamental mechanism for ensuring data integrity in electronic systems. Every entry, change, and deletion in the database is automatically recorded with information identifying who performed the action, when it occurred, what the original value was, and what the new value is. This immutable record protects against undetected data manipulation and supports regulatory inspection by demonstrating the chain of custody for all data throughout the trial.

Regulatory requirements for electronic records, including FDA 21 CFR Part 11 and EU Annex 11, mandate that clinical trial systems maintain audit trails meeting specific criteria. The audit trail must be automatically generated by the system rather than manually created by users. It must capture sufficient information to enable reconstruction of the data history, including the previous value, new value, user identity, date and time, and reason for change where required. The audit trail itself must be protected from modification or deletion, ensuring that the historical record cannot be tampered with. Users must be unable to disable or modify audit trail functionality.

Review of audit trails serves multiple purposes in clinical trial quality management. During routine data cleaning, audit trail review can identify patterns of corrections that may indicate training needs or systemic issues with data collection. During monitoring and auditing, audit trail review enables verification that data changes are legitimate and appropriately documented. During regulatory inspections, audit trails demonstrate that data integrity has been maintained and that any modifications followed appropriate procedures. Systems must provide functionality for audit trail review that is practical for users while maintaining the integrity of the underlying records.