An audit provides an independent evaluation of clinical trial conduct that is separate from and complementary to routine monitoring activities. While monitors work closely with sites throughout the trial, auditors maintain independence and evaluate trial activities from an objective perspective. Audits may be conducted by the sponsor's internal quality assurance unit, by external audit organizations, or as part of regulatory inspections by government authorities.

Sponsor-initiated audits serve as a quality assurance function, helping to identify compliance issues before they are discovered by regulatory authorities and providing objective assessment of trial conduct. These audits may focus on specific sites, particular processes such as informed consent or adverse event reporting, specific phases of the trial, or the overall trial conduct. Audit findings are documented in detailed reports that identify observations and categorize them according to significance, enabling sponsors to prioritize corrective and preventive actions.

The audit process involves systematic review of documentation and may include interviews with site personnel, observation of processes, and facility inspections. Auditors evaluate whether trial conduct conforms to the protocol, whether GCP requirements have been met, whether source documentation supports reported data, and whether regulatory submissions accurately reflect trial conduct. Unlike routine monitoring, audits are typically conducted without advance notice or with limited notice to obtain an accurate picture of normal operations. Audit findings must be communicated to responsible parties and followed up to ensure appropriate corrective actions are implemented.