SELECTION OF NORMAL CONTROL SUBJECTS FOR PSYCHIATRIC RESEARCH - UPDATE ON A MODEL FOR CENTRALIZED RECRUITMENT

A recruitment program for 'normal' control subjects is evaluated with regard to the yield of 'healthy' subjects, the degree to which subject s remain healthy over a number of years, and the rate of subject parti cipation in research. Only 22.4% had no lifetime history of mental ill ness (Never Mentally Ill), 6.8% met the criteria for one episode of a minor mental disorder (MMD), 41.6% were currently healthy but had a mo re serious history of mental illness and 29.9% were currently mentally ill. Diagnostic follow-up found that subjects in the NMI and MMD cate gories did not differ with regard to the rate of interval episodes in themselves or in family members over an average of 27 months. However, subjects in the MMD category were more likely to have a positive fami ly history of mental illness (chi(2)(1)= 21.34; P < 0.001). The longit udinal course of mental health in a combined group of NMI and MMD subj ects was predicted by sex of the subject (chi(2)(1)= 4.03; P < 0.05), but not by age or family history of mental illness. These findings sug gest that investigators selecting 'healthy' control subjects consider the probability that a currently healthy individual will have episodes of mental illness in the future. (C) 1998 Elsevier Science ireland Lt d. All rights reserved.