RESUMEN
Large, long term research studies present recruitment challenges that can be met with collaborative approaches to identify and enroll participants. The Osteoporotic Fractures in Men Study (MrOS), a multi-center observational study designed to determine risk factors for osteoporosis, fractures and prostate cancer in older men, recruited 5995 participants over a 25-month period. Enrolling a cohort that represented the race and age distribution of each community, and developing interest in an older male cohort about a condition commonly thought of as a "women's disease," were major recruitment challenges. During the start-up phase, recruitment challenges and strategies were analyzed and collective approaches were developed to address ways to motivate the target population. Key methods included mailings using community and provider contact lists; regional and senior newspaper advertisements; and presentations targeted to seniors. Sites used a centrally developed recruitment brochure. Response to mass mailings at some sites surpassed 10-15% and appointment show rates averaged above 85%. The final number enrolled in MrOS was 5% more than the original recruitment goal of 5700. Minority recruitment was enhanced through the use of the Health Care Financing Administration and other databases that allowed for targeted recruitment. Overall, minority enrollment was approximately 10.56% of the cohort (244 African American, 191 Asian). Men age>80 were enthusiastic and represent about 18% of enrollees. Through a coordinated approach of developing and refining recruitment strategies and materials, sites were able to adapt their original strategies and complete recruitment ahead of schedule.