26 Source Data Verification & Risk-Based Monitoring

26.1 Source Data Verification (SDV)

26.1.1 Definition

Comparison of data recorded in the EDC against source documents to ensure accuracy, completeness, and reliability.

26.1.2 Typical SDV Areas

Informed consent dates
Eligibility criteria
Primary endpoint data
Safety data (AEs / SAEs)
IP dosing records

26.2 Risk-Based Monitoring (RBM)

26.2.1 Principles

Focus on critical data and processes
Reduce unnecessary SDV
Identify systemic risks early

26.2.2 CRA Responsibilities

Apply monitoring plan consistently
Escalate emerging risk trends
Document rationale for targeted SDV

Oncology-Specific Considerations

Cycle 1 often requires 100% SDV
Dose modifications and delays require close source review
Tumor assessments (e.g., RECIST) must be traceable to source

Vaccine Trial Consideration

Monitoring in vaccine trials may emphasize visit timing adherence, consent accuracy, and rapid data entry due to time-sensitive endpoints.