Healthy sleepers are rare: Problems and success rates in establishing a control group for sleep studies

Abstract

A large and representative controlgroup is paramount for establishing normative values for sleep in middle-aged persons. However, it is very difficult to recruit normalsleepers. From 286 volunteers who responded to an advertisement for healthy sleepers, only 47 finishedthe study. We excluded 221 after evaluation of their medicalsleep history, generalhealth data, and results of physical examination. Wefurther excluded 18 volunteers after nighttime polysomnography. We finally eliminated from the study 37.5% of the volunteers whoentered the screening procedure, on grounds of their sleep disturbances. Our study reveals that investigators face major difficulties whentrying to establish a controlgroup of healthy sleepers from the middle-aged population. Sufficient interest on the part of potentialtestpersons does in fact exist, but their generalhealth—and, especially, previously undiscovered sleep disorders—frequently prohibit theirinclusion. Internationaland interdisciplinary cooperation is necessary to establish a sufficiently large controlgroup for both clinicalandresearch purposes. © 2003 Nature Publishing Group.