Patient recruitment encompasses the diverse methods and communications used to identify individuals who may be eligible for clinical trial participation and motivate them to learn more about the study opportunity. Effective recruitment balances the scientific need to enroll adequate numbers of participants within reasonable timeframes against the ethical imperative to provide accurate, non-coercive information that enables informed decision-making. Recruitment failures represent one of the most common reasons for trial delays and cost overruns.

Recruitment strategies vary based on the disease area, study design, and patient population characteristics. Traditional approaches include physician referrals within the investigator's practice, referrals from colleague physicians, medical record screening to identify potentially eligible patients, and advertising through various channels. Digital recruitment methods have expanded options significantly, enabling targeted outreach through social media, search engine marketing, patient advocacy organization partnerships, and online patient communities. Each recruitment channel has distinct advantages, costs, and regulatory considerations.

All recruitment materials and methods require IRB/IEC review and approval before implementation. Advertising must be accurate and not misleading regarding the nature of the research or potential benefits. Recruitment messaging must clearly identify the opportunity as research rather than clinical care, avoid claims of therapeutic benefit unsupported by evidence, and refrain from emphasizing payment in ways that might constitute undue inducement. The recruitment process sets expectations for potential participants and influences their understanding and trust throughout trial participation.