CROs are not selecting sites on reputation or facility quality. Selection is data-driven, and the data consists of five performance metrics tracked per site, per study, and over time. Sites that understand and actively manage these metrics improve their study acquisition rate in a measurable, predictable way.
First-Patient-In Speed
FPI speed — days from site activation to first enrolled patient — is rated by a plurality of CRO decision-makers as the most important site quality factor. Sites with enrollment infrastructure in place before activation consistently achieve faster FPI than sites building recruitment approaches post-activation. Every day of delay costs the sponsor money and creates timeline risk.
Screen Failure Rate
Screen failure rate is the percentage of patients entering the screening process who fail eligibility before enrollment. Rates above 50 percent indicate that pre-screening is not adequately filtering patients before the full screening visit. This wastes study budget, coordinator time, and patient goodwill. AI-assisted pre-screening directly addresses this metric.
Database Query Rate
Queries are corrections requested when submitted data contains errors or omissions. High query rates tell sponsors that data entry processes are unreliable. Sites with low query rates — because data collection is standardized and validated at entry — earn continued selection. High query rates earn monitoring scrutiny and eventually removal.
Protocol Deviation Rate
Deviations occur when the site departs from protocol — missed assessments, procedures outside windows, post-enrollment eligibility violations. High deviation rates signal understaffing or insufficient protocol compliance infrastructure. Each deviation requires documentation, investigation, and often sponsor notification.
Enrollment Velocity Over Time
Consistent enrollment week over week matters as much as total numbers. Sites that exhaust their referral network in month one and then stall create timeline unpredictability. Sites with ongoing physician outreach producing steady referral flow enroll consistently — and sponsors strongly prefer predictable over erratic.