How to Run a Clinical Trial Feasibility Assessment Before You Commit

Most research sites answer a sponsor's feasibility questionnaire before they've done any internal analysis. They estimate patient numbers from memory, assume staff can absorb one more study, and say yes to a protocol they haven't read closely enough. Months later, they're behind on enrollment and the sponsor is calling weekly. The internal assessment comes first. This guide is that assessment.

What a Feasibility Assessment Actually Evaluates

A feasibility assessment is a structured evaluation of whether a specific study can succeed at a specific site. The keyword is “specific” on both sides. A site that consistently excels in Phase II oncology may be entirely wrong for a pediatric vaccine study. The assessment exists to answer one question: given this protocol and this site, is a reliable enrollment outcome realistic?

Credible feasibility frameworks evaluate six domains (PMC, 2023): research team readiness, infrastructure and equipment, study management capability, data collection and quality systems, ethics and safety procedures, and patient population access.

Most sites can evaluate five of those six domains themselves, in an afternoon. Patient population is the sixth. It requires real data, and it is where most internal assessments break down.

Why You Should Assess Yourself Before the Sponsor Does

When a site answers a sponsor questionnaire without prior internal analysis, the estimates tend to run optimistic. Enrollment projections come from intuition rather than chart reviews. Staff capacity gets assessed in the abstract rather than against the actual current study load. The result is a committed enrollment number the site cannot deliver.

The consequences extend beyond one study. A site that consistently misses enrollment targets gets flagged. It receives fewer future opportunities, gets passed over during competitive site selection, and earns a reputation for unreliability regardless of how strong its patient care is.

The financial stakes make this sharper. Phase II per-patient site fees typically run $15,000 to $40,000 (ProRelix). Phase III fees average $6,100 per patient, with a range of $2,100 to $19,300 depending on visit burden and procedure complexity (Journal of Clinical Oncology). A single study with a 10-patient target represents up to $150,000 in potential site revenue. Committing to that and missing the target is not a missed opportunity in isolation. It costs you the next one.

Running your own internal assessment before responding takes two to four hours. It turns a reactive answer into a defensible one. It gives you the basis to negotiate a modified enrollment target if the numbers don't support the original ask. And it protects the sponsor relationship, because you are delivering what you actually committed to.

Step 1: Map Your Patient Population Against the Protocol

This is the hardest step, and the one most sites skip.

Mapping your patient population means taking the protocol's inclusion and exclusion criteria and running them against your actual patient database. Not the diagnosis count. Not the total patients in the therapeutic area. The chart-eligible patients who meet every criterion, are likely to consent, and are available during the enrollment window.

The process runs through four levels:

The number that comes out of this funnel is your realistic enrollment ceiling. Not a target. A ceiling.

Two mistakes show up repeatedly at this step.

Forgetting competing trials. If two other studies are currently enrolling in the same diagnosis, those patients may already be screened or committed. Competing enrollment is one of the most common causes of missed targets at sites that had the right population on paper.

Ignoring the enrollment window. A six-month period with a 90-day screening window is not the same as six months of open access. The effective window is shorter than it looks on the protocol timeline.

The Clinical Enroll free enrollment feasibility report runs this analysis using ClinicalTrials.gov protocol data and patient population density by ZIP code. If you want a data-backed projection before your answer goes back to the sponsor, run it first.

Step 2: Audit Your Site Capacity

Once you have a realistic enrollment ceiling from Step 1, the question becomes: can your site actually run this study on top of what it already has open?

Start with a simple inventory. List every active trial. Map the coordinator load per study, in hours per week. Then check whether adding this protocol creates a bottleneck anywhere.

Protocol complexity matters more than study count. A Phase III cardiovascular study with monthly visits requires fundamentally different coordinator time than a Phase I oncology study with weekly assessments, infusion visits, and real-time safety reporting. Two studies of the first type may be manageable. One of the second type, alongside two others, may not be.

Infrastructure is the second layer. Check whether this protocol requires equipment or facility space that existing studies already use. An MRI-dependent protocol at a site with one scanner and two other imaging-heavy studies creates a scheduling conflict that will eventually affect enrollment.

The most overlooked factor is study management bandwidth at the coordinator level. Coordinators manage visits, regulatory submissions, sponsor calls, adverse event reporting, and source documentation. When that bandwidth fills up, enrollment slows. The first study to suffer is always the most recently added one. If your capacity review produces any “it depends” answers, get more specific before committing.

Step 3: Evaluate the Protocol Itself

Not every protocol is a good fit for every site, even when the patient population exists and the capacity is there.

Three factors predict site-level difficulty: visit burden, eligibility restrictiveness, and procedure complexity.

Score each of these three factors on a simple low, medium, or high scale. A study scoring high on all three is not necessarily a no. It is a study that requires either more resources or a lower enrollment commitment, and you should know that before you answer the questionnaire.

Putting It Together: The Yes/No Decision

The internal feasibility assessment comes down to three questions. The quality of your answers determines your response to the sponsor.

If all three answers are yes with confidence, commit.

If any answer is uncertain, three options exist: negotiate a lower enrollment target, negotiate a longer enrollment period, or decline. Decline is a legitimate response. A site that declines studies it cannot deliver maintains its standing with sponsors. A site that accepts and underperforms loses that standing.

Sites that build this framework into their standard operating procedure become preferred sites. Not because they accept every study offered, but because when they commit, they deliver.

For a data-backed answer to Question 1, the enrollment feasibility report gives you patient population density and protocol-level context before your answer goes back to the sponsor. For a deeper look at what happens when enrollment falls short mid-study, see Clinical Trial Enrollment Challenges: Why Sites Miss Goals.