Recruiting an underserved, difficult to reach population into a cancer trial: Strategies from the

BACKGROUND/

aimsSexual minorities are small and under-researched populations that are at disproportionate risk for cancer and poor cancer outcomes. Described as a "hidden population," the principal research challenge has been to develop effective methods to identify and recruit such cancer patients into cancer studies. Online recruitment strategies, as well as targeted clinic recruitment using patient-entered sexual orientation and gender identity data from electronic medical records have potential to transform recruitment, but studies testing the effects of how to recruit using these have not been published.

methodsIn 2019, we conducted a naturalistic, three-arm, stratified prospective study to compare three recruitment strategies: (a) clinic based recruitment of prostate cancer patients from gay health and urology clinics; (b) directly from the gay community; and (c) online recruitment (through cancer support, sex/dating, and social sites). For each strategy, we estimated time, workload, and direct costs involved. To study how recruitment strategy may affect sampling, we tested for retention rates, demographic and outcome differences across sites. Using these methods, we successfully recruited 401 gay and bisexual prostate cancer patients into a randomized, controlled, 24-month trial testing an online sexual and urinary rehabilitation curriculum tailored for this population.

resultsThere were seven key results. First, it is possible to recruit substantial numbers of sexual minority men into prostate cancer studies provided online recruitment methods are used. Second, we observed big differences in dropout during study onboarding by recruitment source. Third, within online recruitment, the online sex/dating application (app) was the most successful and efficient, followed by the cancer support site, and then the social networking site. Fourth, while clinics were the cheapest source of recruitment, they were time intensive and low in yield. Fifth, the cancer support site and sex/dating app recruits differed by several characteristics, with the former being more rehabilitation-focused while the latter were younger and more sexually active. Sixth, we found almost no differences in outcomes across the three online recruitment sites. Seventh, because retention in online studies has been a concern, we confirm very low attrition at 3- and 6 months into the trial.

conclusionFor sexual minority cancer research, more research on how to use sexual orientation and gender identity electronic medical record data for clinic-based recruitment is needed. For other small or hard-to-reach populations, researchers should compare and publish online versus offline recruitment strategies.