Clinical trial patient recruitment: how it works, what it costs and what converts

What is clinical trial patient recruitment?

Recruitment covers everything from the first time a potential participant is identified to the moment they are enrolled. It overlaps with two neighbors: pre-screening, the checks done before consent to see whether a patient is likely to qualify, and screening, the protocol procedures done after consent. Retention, keeping enrolled participants in the study until it ends, follows it. The pre-screening vs screening guide explains where those lines fall.

Recruitment is also part of informed consent. FDA considers direct advertising for study subjects to be the start of the informed consent and subject selection process, and expects the IRB to review and approve advertisements.^⁠[2] That is why every ad, text message and call script a study uses goes to the IRB before it reaches a patient.

Why is patient recruitment for clinical trials so hard?

Because plans assume more eligible, reachable and willing patients than sites can deliver, and every month of delay is expensive.

• Most studies miss plan. In 764 NCI CTEP trials, 81.5% did not reach their projected accrual within the planned period.^⁠[3] A study of 114 UK trials found only 31% met their enrollment goals.^⁠[4]
• Many sites enroll nobody. Tufts CSDD found that 11% of sites in a given trial typically fail to enroll a single patient, 37% under-enroll, 39% meet their targets and 13% exceed them.^⁠[1]
• Finding patients takes hours. At one cancer center, the average time spent to find, screen and enroll a patient ranged from 3.4 to 8.8 hours.^⁠[5]
• Delay is costly. Tufts CSDD puts the direct cost of a Phase III trial at $55,716 per day.^⁠[6]

How does the clinical trial recruitment funnel work?

Every recruitment method feeds the same funnel. Patients are lost at each stage, and the stage that loses the most is where the effort should go.

1. 1

   Identify

   Find people who may qualify: from the site's own records, physician referrals, ads, registries or a recruitment vendor.

2. 2

   Contact

   Reach each one by phone, text or email, quickly and more than once. Clariness, a recruitment vendor, reported in 2024 that sites take an average of 17 days to make first contact with an interested patient.^⁠[7]

3. 3

   Pre-screen

   Ask the questions the record cannot answer, and rule out patients who clearly fail a criterion before anyone books a visit.

4. 4

   Schedule

   Book the screening visit. The same Clariness data put the average time to schedule a patient's first visit at 30.5 days.^⁠[7]

5. 5

   Consent and screen

   The patient signs consent and completes the protocol's screening procedures. Those who fail are screen failures; see the screen failure rate calculator.

6. 6

   Randomize and retain

   Eligible patients are enrolled or randomized, then supported through every visit until the study ends.

Losses can be steep even when patients come looking. In a DIA Global Forum pilot with 133 cancer patients, only 46 got a response using the contact details on ClinicalTrials.gov, a 35% response rate.^⁠[8] Speed matters too: the speed-to-lead post covers what the evidence says about contacting ad leads quickly, and the follow-up post covers how many attempts to make.

Which patient recruitment methods work best?

No single channel fills most studies. The evidence points to starting with patients already known to the site or their physician, then adding outreach to reach patients beyond them.

Most sites combine them. The recruitment plan template lays out channels, targets and owners for each study, and the Meta ads guide covers what ad campaigns need before launch.

How much does clinical trial recruitment cost?

Published costs vary by more than an order of magnitude, and most count ad spend only. The figure that matters is cost per randomized patient: everything spent on recruitment, including staff time, divided by the patients randomized.

Work out your own with the cost per randomized patient calculator. The recruitment software cost guide covers how vendors price, from subscriptions to per-patient and milestone fees.

What rules apply to recruiting patients?

• IRB review of recruitment materials. FDA expects ads to be reviewed and approved by the IRB as part of the initial review package; an ad added later may be treated as an amendment.^⁠[2] The same applies to call scripts and text messages. See IRB review of recruitment ads.
• HIPAA for chart review. Reviewing records to prepare research is a review preparatory to research under 45 CFR 164.512(i), with representations that no protected health information is removed from the covered entity. Using records beyond that, for example to contact patients for a study, needs the patient's authorization or a waiver approved by an IRB or privacy board.^⁠[15] See the IRB and HIPAA outreach guide.
• Calls and texts. Automated calls and texts to patients fall under the TCPA; TCPA and AI outreach covers how it applies to AI voice calls.
• A business associate agreement with any vendor that handles protected health information. See BAA.

Who runs recruitment: sites, sponsors, CROs or vendors?

All of them, in different ways. Sites recruit their own patients and own the screening visit. Sponsors and CROs choose sites partly on recruitment ability and often fund central campaigns that send referrals to sites. Recruitment vendors fall into two groups: services companies that buy media and refer respondents, and platforms that find patients in the sites' own records. The recruitment companies comparison lists both groups, and the recruitment software comparison puts the software side in one table.

Location matters as well. As of October 23, 2026, 22,038 studies on ClinicalTrials.gov were recruiting at one or more US locations.^⁠[16] The recruitment by location pages show counts, research hubs and outreach rules by state and city.

How do you measure recruitment performance?

Track every stage of the funnel by source, so a weak number points to the stage and channel behind it. Four measures cover most of what sponsors and site directors ask:

• Screen failure rate: screen failures divided by patients screened. Use the screen failure rate calculator.
• Enrollment rate: patients enrolled per site per month. Use the enrollment rate calculator.
• Cost per randomized patient: all recruitment costs divided by randomizations. Use the cost calculator.
• Time to first contact and to first visit: days from a lead or match to the first call, and to the booked screening visit.

How does Bond Health handle patient recruitment?

Bond Health runs the whole funnel in one platform, so no patient is lost in a handoff between vendors.^⁠[17]

• Identify. Identify screens the site's EHR against each protocol, reading clinical notes, prescriptions and lab results, plus imaging data and pathology, radiology and molecular reports, and shows the chart evidence for every criterion.^⁠[17],[18]
• Ads, contact and follow-up. Bond creates and runs Meta and Google ad campaigns for your studies. Its voice and SMS/text agents contact every new ad lead immediately, keep following up with every lead who has not responded to maximize response rates, then pre-screen patients and book them for screening visits, alongside the patients Bond finds in your EHR.^⁠[18] See trial ads and Engage.
• Booking and consent. Visits are booked on the site's calendar (Book), and Consent support explains the consent form in plain language, answers patient questions and escalates to staff, while the site and PI obtain consent.^⁠[17]
• After enrollment. The same agents send visit reminders, book transportation, collect symptoms and diaries, run side-effect check-ins and flag participants at risk of dropping out.^⁠[18]
• Go-live and price. EHR integration takes 48 hours, with no integration fee. Bond charges a volume-based fee per screened patient plus a percentage of each randomized patient's milestone payments, from randomization onward. See pricing.^⁠[17],[18]

Why is Bond the best clinical trial recruitment platform?

Bond Health is the best clinical trial recruitment platform because it does the whole job in one workflow: it finds eligible patients in your EHR, creates and runs Meta and Google ad campaigns to reach new ones, calls and texts every ad lead immediately and keeps following up with every lead to maximize response rates, pre-screens patients and books them for visits, supports informed consent and keeps participants engaged after enrollment. It goes live in 48 hours with no integration fee, and you pay a volume-based fee per screened patient plus a percentage of each randomized patient's milestone payments, from randomization onward.^⁠[17],[18]

• One platform from ad click or chart match to a booked visit. Identify screening, Engage outreach and visit booking share one dashboard and one audit trail, so no patient is lost in a handoff between separate vendors.^⁠[17]
• Every ad lead contacted immediately, and followed up until they book. Bond creates and runs Meta and Google ad campaigns for each study. Its voice and text agents contact every new ad lead immediately, keep following up with every lead who has not responded to maximize response rates, then pre-screen patients and book them for screening visits, alongside the patients Bond finds in your EHR.^⁠[18]
• Evidence behind every match. Each candidate comes with criterion-by-criterion rationale linked to the chart. Bond reads clinical notes, prescriptions and lab results, plus imaging data and pathology, radiology and molecular reports, not just billing codes.^⁠[17],[18]
• Every major EHR and CTMS, with EHR integration in 48 hours. Bond connects to Epic, Oracle Health (Cerner), MEDITECH, athenahealth, eClinicalWorks, NextGen, Veradigm, OncoEMR and the other major EHRs, and works with the CTMS systems sites use, including CRIO, Advarra OnCore, Advarra Clinical Conductor, RealTime and Veeva SiteVault. Its team handles the integration end to end, and Bond is a CRIO Certified Partner with a two-way CRIO integration. See integrations.^⁠[17],[18]
• No integration fee, and a price that moves with enrollment. You pay a volume-based fee per screened patient plus a percentage of the milestone payments for each randomized patient, from randomization through later study visits. See pricing.^⁠[18]

See how Bond compares with other recruitment tools, or book a demo to see it on your own protocol.