About the Study

Predictors and Mechanisms of Conversion to Psychosis

There have been three projects led by the North American Prodrome Longitudinal Study (NAPLS) consortium. These three projects NAPLS-1, NAPLS-2 and NAPLS-3 have focused on studying predictors and mechanisms of conversion to psychosis of youth at clinical high risk (CHR) of psychosis. NAPLS-3 was funded under the collaborative UO1 mechanism of NIMH. It is a longitudinal study with nine NAPLS sites (Calgary, UCLA, UCSD, UNC, UCSF, Yale, Harvard, Emory and Zucker Hillside Hospital in New York) with a potential sample of 774 participants at CHR of psychosis and 100 healthy controls generating one of the largest clinical high risk samples and highest number of converted subjects within the field, and provides statistical power and scientific scope that cannot be duplicated by any single study. Assessments included both clinical (symptoms, functioning, neurocognition) and biomarker assessments (MRI, EEG, cortisol and blood draws). Each site contributed an area of uniqueness to the overall study by leading a "task force" in a domain of assessment: clinical (J. Addington, Calgary), functional assessment (B. Cornblatt, ZHH), neurocognition (B. Stone, Harvard), neuroimaging (T. Cannon, Yale), stress hormones (E. Walker, Emory), electrophysiology (K. Cadenhead, UCSD; D. Mathalon, UCSF), treatment (S. Woods Yale) and genomics (D. Perkins, UNC; M. Tsuang, UCSD). The Clinical Assessment Core formed the foundation on which the Biomarkers Assessment Core interprets their findings since currently our definitions of schizophrenia are clinically determined. The Biomarkers Core examined potential biological mechanisms of illness onset/progression in the neuroanatomical, electrophysiological, neurohormonal, and neurocognitive domains.

Since NAPLS-2 and NAPLS-3 only included 2-year follow-ups, it is unclear what the longitudinal trajectories are of these young people who initially presented with attenuated psychotic symptoms both in terms of clinical outcome and functioning. We are now conducting a longitudinal 5-13 year follow-up of all previous NAPLS-2 and NAPLS-3 participants.

Anyone who was part of NAPLS-2 or NAPLS-3 can contact us at 403-210-8740 or email This e-mail address is being protected from spambots. You need JavaScript enabled to view it