Recruitment of elderly volunteers for a multicenter clinical trial: the SHEP pilot study

Few large trials have involved the elderly, and little is known about the feasibility of recruiting such participants for study and the validity of inferences drawn from them. This article reviews the recruitment experience of the Systolic Hypertension in the Elderly Program (SHEP) pilot study. That program involved five clinical centers, and contacted approximately 75,000 persons in order to enroll a cohort of 551 individuals over 60 years old isolated systolic hypertension. The enrolled cohort was somewhat older and more highly educated than those screened. Except for deliberate oversampling of blacks and those over 70 years old, the enrolled population resembled the U.S. population, although individuals in the SHEP group were initially healthier, and more likely to have had some college education than those in the general population. There was substantial variation among sites in number of staff hours spent per participant recruited. The SHEP experience indicates that older persons are willing to volunteer for clinical trials research and that problems of inference are probably not any greater for that age group than for any other.