The clinical research associate serves as the sponsor's primary representative in overseeing trial conduct at investigational sites. This role, sometimes referred to as a clinical monitor, requires a unique combination of scientific knowledge, regulatory expertise, and interpersonal skills to effectively evaluate site performance, identify issues requiring corrective action, and maintain productive relationships with site personnel. CRAs typically hold degrees in life sciences or nursing and receive specialized training in GCP, therapeutic areas, and monitoring practices.

Monitoring activities performed by CRAs serve multiple purposes: verifying that participant rights and safety are protected, confirming that reported trial data are accurate, complete, and verifiable from source documents, and ensuring that the trial is conducted in compliance with the protocol, GCP, and applicable regulations. These objectives are accomplished through a combination of on-site visits, remote monitoring activities, and centralized review of data patterns and trends.

The evolution of monitoring practices has significantly affected the CRA role. Traditional monitoring emphasized complete source document verification during frequent on-site visits. Current approaches, as reflected in ICH E6(R3), emphasize risk-based monitoring that allocates monitoring resources based on the specific risks associated with each trial and site. This evolution requires CRAs to exercise greater judgment in identifying sites and data requiring focused attention, while leveraging technology and centralized monitoring to supplement their direct observations.