North American Prodrome Longitudinal Study

This chapter provides a summary of a landmark study on schizophrenia. The question studied was “In patients identified clinically to be at high risk for psychosis, which variables (or their combinations) best predict conversion to schizophrenia or another psychotic disorder?” Starting with that question, it describes the basics of the study, including funding, study location, who was studied, how many patients, study design, study intervention, follow-up, endpoints, results, and criticism and limitations. This study demonstrates that presence of some characteristics can better prognosticate conversion of a prodromal state to a psychotic disorder. Finally, the chapter briefly reviews other relevant studies and information, discusses implications, and concludes with a relevant clinical case.