First-episode psychosis: Part I. Editors' introduction.

Until recently, there has been a conspicuous lack of studies regarding the earliest phases of psychotic illness, with most research on schizophrenia and related disorders focusing on chronically ill patients. Currently, however, a number of investigators have turned their attention toward this topic, exploring the conceptual issues involved in defining the onset of psychosis, using case registers and population-based samples to do crucial epidemiologic studies on the course of schizophrenia, and developing mechanisms for identifying patients with first-episode psychosis and entering them into active research protocols. The issue of the Schizophrenia Bulletin is devoted to articles representing this full range of conceptual and empirical work on first-episode psychosis. The ultimate goal is for researchers working in this area to develop a network to enhance the sharing of concepts and data, with the eventual possibility of developing combined data bases and collaborative studies.