Benchmarks and tools

Enrollment forecast calculator for clinical trial sites

By TrialNotice · Updated
Research coordinator marking weekly enrollment targets on a wall calendar in a clinic office
Short answerWork backward from the deadline: divide the remaining randomizations by the weeks left, divide again by one minus your screen failure rate to get weekly screens, then by your consent rate to get weekly candidates. The calculator below does it for you and flags whether your current pace will miss the deadline.
Line chart comparing a target enrollment pace of 12 patients in 24 weeks with a slower current pace

Enrollment forecast calculator

Defaults are illustrative. The screen failure default is the Tufts CSDD average of 36.3% (Tufts CSDD).

Why forecast this way?

Because sponsors have learned to discount site estimates. Getz reports that even adjusted feasibility estimates are accurate less than 10% of the time by sponsor accounts, and the majority of trials run late (Applied Clinical Trials). A forecast that shows its math, and is updated weekly, earns trust.

What do you do when the forecast says you will miss?

Add candidates, not hope. In a typical trial 37% of sites under enroll (Tufts CSDD). The fix is more patient sources started early enough to matter, including referring physicians who already see your population. See how to meet an enrollment deadline.

Get your study in front of the right local physicians

TrialNotice builds a physician referral pipeline around one active study. We identify relevant local physicians within driving distance of your site, send study aligned direct mail, follow up by email and LinkedIn, track engagement with recipient level QR codes, and route warm responses into your site team's workflow.

Talk to TrialNotice

Sources

  1. Applied Clinical Trials, "Can Recruitment and Retention Get Any Worse?" (Tufts CSDD screen failure study)
  2. Getz K., "Is Investigative Site Feasibility Feasible?" Applied Clinical Trials
  3. Tufts CSDD, patient recruitment and retention practices study (Jan 2013), via Fierce Biotech

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