Costs of recruiting couples to a clinical trial

Multiple barriers contribute to the slow recruitment of participants to research studies, which in turn extends the time required to translate promising scientific discoveries into proven therapeutic interventions. A small but growing literature is developing on the extraordinary costs of recruiting participants to studies, and thereby demonstrating that underestimating the cost of participant recruitment can contribute to these recruitment problems. These recruitment challenges and costs are exacerbated when the participants' study eligibility is determined by relatively narrowly defined illness parameters. Recruitment challenges are further compounded when dyads (two individuals engaged in a sociologically significant relationship, such as husbands and wives, siblings or extended families) must be recruited to an illness-focused study. For these latter groups, there are no data to guide researchers in how to anticipate those participant recruitment costs. This paper describes the staff costs for a variety of strategies used to recruit participants to a randomized supportive care study for couples who were within 18 months of a prostate cancer diagnosis. Pegged to the value of the U.S. dollar for the period, the average cost of staff time was $288 per recruited and enrolled dyad, plus a promised additional $100 incentive for study retention. Within the strategies used, the staff costs per recruited dyad ranged from $152 to $1688. Accrual per strategy ranged from 0 to 107 enrolled couples. When asked for secondary sources of information about the study, many participants reported more than one source of study referral, reflective of the multifaceted recruitment strategies deployed. In spite of innovative, culturally competent, and broad based recruitment methods, attainment of a diverse sample was difficult to accomplish in this study. Having estimates of the actual cost of recruiting dyads to research studies can help investigators prepare realistic study budgets.