A Protocol Deviation (PD) is any departure from the approved protocol, consent process, or study procedures, whether planned or unplanned.
Deviations may involve missed visits, incorrect dosing, late assessments, eligibility errors, or documentation gaps that can affect participant safety or data reliability. Deviation management typically includes documentation, root-cause review, impact assessment, and reporting based on sponsor and IRB requirements. Significant or recurring deviations may trigger corrective and preventive actions (CAPA) and closer oversight. Consistent deviation tracking supports inspection readiness and protects study integrity.