Site feasibility questionnaires are often treated as a formality — a form sites fill in to confirm interest, reviewed quickly to keep site activation on schedule. Treated that way, they miss their actual purpose: surfacing the operational realities that predict whether a site will actually enroll, not just whether it says it can.
Ask about actual patient flow, not catchment population
A site's stated catchment population is a poor predictor of enrollment. Ask instead how many patients matching your specific inclusion and exclusion criteria the site has seen in the last 12 months, and how many of those were already enrolled in a competing trial. The gap between "patients we could theoretically see" and "patients actually available to this study" is where most enrollment shortfalls originate.
Ask who does the work, not just who signs the form
The principal investigator's experience matters, but day-to-day enrollment performance is driven largely by the study coordinator — their availability, their existing workload across other trials, and how long they have worked with the PI. A feasibility questionnaire that does not ask about coordinator capacity is missing the variable most closely correlated with actual site performance.
Ask about competing trials explicitly
Sites rarely volunteer that they are running three other trials with overlapping eligibility criteria, because doing so risks losing the opportunity. Ask directly, by indication and phase, what else is competing for the same patient population at that site right now. A site that is honest about competition is generally a more reliable partner than one that is not.
Ask about historical enrollment performance, with evidence
Self-reported enrollment history is optimistic by default. Where possible, ask for enrollment data from a comparable recent study — actual numbers against actual projections, not general claims of strong performance. A site willing to share a study where they underperformed, and explain why, is telling you more than one that only shares its successes.
Ask about regulatory and IRB/EC timelines realistically
Sites frequently underestimate their own regulatory and ethics committee timelines, particularly for first-time collaborations. Ask for the actual timeline achieved on their two most recent studies, not an estimate, and build your site activation plan around that evidence rather than the site's stated best case.
Weight the questionnaire toward predictive questions
Many feasibility questionnaires spend most of their length on facility and equipment checklists that rarely predict enrollment failure, and too little on the operational questions above that do. A well-designed questionnaire is shorter, more specific, and harder for a site to answer with generic reassurance.
Where a structured scorecard helps
Our Site Feasibility & Selection Scorecard gives study teams a consistent, weighted framework for comparing sites on the questions that actually predict enrollment, rather than relying on unstructured feasibility calls. For programmes designing a full site strategy, our Clinical Trial Consulting service includes feasibility strategy and site selection framework development.