Patient recruitment

How to recruit more patients for a clinical trial at your site

By TrialNotice · Updated
Clinical research coordinator in navy scrubs talking with an older male patient in a bright consultation room
Short answerSites recruit more patients by working three sources at the same time: eligible patients already in their own records, people reached through advertising, and patients referred by local physicians who already treat the condition. Physician referral is the most underused of the three. Physicians refer less than 0.2% of their patients into trials, yet most patients say they would start a trial search by asking their doctor.

Where do clinical trial patients actually come from?

CISCRP's 2025 Perceptions and Insights study asked people who had participated in a trial how they found out about it: 22% said online and 16% said their own doctor. The same study found understanding, awareness, and willingness to participate all declined since 2023, though 87% remained somewhat or very willing (Citeline summary of CISCRP 2025). In CISCRP's 2017 study, 58% said they would begin a search for a trial by asking their doctor (CISCRP).

The takeaway: patients prefer to hear about trials from their doctor, but relatively few actually do. That is the gap a site can close.

Source one: patients already in your records

Start with the patients your site or affiliated practice already sees. Chart review against the protocol's criteria is the fastest source to activate and costs the least. Its limit is volume: once your own panel is screened, it does not refill quickly.

Source two: advertising

Among respondents in CISCRP's 2025 study who prefer to hear about studies online, social media was the top choice, with Facebook named most often (Citeline). Ads reach people who self identify with a condition. That can create volume, and every response still has to be screened against the protocol.

Source three: local physician referrals

Referring physicians send patients whose diagnosis they already manage. The channel is badly underused: physicians refer a median of five patients into trials per year (Getz), and they cite missing study information and time as the reasons (Tufts CSDD).

When sites invest in it, it works. A Phase 1 unit that opened a memory clinic and engaged community physicians received 98 referrals and enrolled 16 patients in 2017, and grew its referral network by 30 physicians within a 20 mile radius (Journal of Prevention of Alzheimer's Disease). A neurology site in Connecticut made community clinician referrals its top source of new patients (Applied Clinical Trials).

What is a practical plan to recruit more patients?

  1. Screen your own records first for fast early enrollment.
  2. List the physicians who treat your study population within driving distance of the site.
  3. Send each one a one page study summary with a named referral contact. See what to put in the letter.
  4. Follow up by email and LinkedIn, and prioritize physicians who engaged.
  5. Close the loop on every referral so physicians refer again.
  6. Add advertising where volume is still short, with screening capacity ready.

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. CISCRP, 2017 Perceptions and Insights Study: Decision Making Process
  2. Citeline, Patient Recruitment Pulse (Jan 2026) on the CISCRP 2025 Perceptions and Insights Study
  3. Ken Getz, Applied Clinical Trials, "Rebooting the Statistic That 5% of Eligible Patients Participate in Clinical Trials"
  4. Applied Clinical Trials, "Tufts CSDD Study Explores Low Recruitment Rates"
  5. Journal of Prevention of Alzheimer's Disease abstract on a memory clinic within a Phase 1 unit
  6. Applied Clinical Trials, "Building a Physician Referral Network: A Case Study"

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