Multiple-risk cohorts and segmenting risk as solutions to the problem of false positives in risk for the major psychoses.

This paper briefly reviews the past promise, current results, and problems that have resulted from application of the risk group approach to understanding the etiology of the major psychoses. The ultimate objective is to stimulate a change in methods that it is hoped will lead to the knowledge required to warrant intervention. Methods of intervention are not reviewed because it is considered more important at this time to improve our understanding of the life course of these disorders. Interventions can be justified when a body of well-agreed-upon findings has accumulated indicating the developmental pathways to the major psychoses, including the situational contexts. It is assumed that the timing and mode of intervention will be evident when these pathways have been delineated.