North American Prodrome Longitudinal Study: a collaborative multisite approach to prodromal schizophrenia research

Schizophr Bull. 2007 May;33(3):665-72. doi: 10.1093/schbul/sbl075. Epub 2007 Jan 25.


This article presents the rationale, design, and preliminary findings of the North American Prodrome Longitudinal Study (NAPLS), a collaborative, multisite investigation into the earliest phase of psychotic illness. We describe how 8 independently conceived research projects were integrated methodologically, how diagnostic reliability was achieved across sites on the Structured Interview for Prodromal Syndromes, and how baseline and follow-up data were aggregated for 888 at risk and comparison subjects. Data are presented describing the demographic, academic/work, and diagnostic characteristics of 3 relevant subgroups: persons at heightened clinical risk for psychosis, help-seeking comparison subjects, and nonpsychiatric controls. The NAPLS data set will be used to explore a series of questions related to prodromal psychosis, including the descriptive phenomenology of currently accepted diagnostic criteria, conversion rates over a 30-month period, predictors of psychosis onset and functional disability, and the impact of early treatment on the course of prodromal symptoms.

Publication types

  • Multicenter Study

MeSH terms

  • Adolescent
  • Adult
  • Cooperative Behavior*
  • Female
  • Humans
  • Longitudinal Studies
  • Male
  • Meta-Analysis as Topic
  • Multicenter Studies as Topic
  • North America
  • Outcome Assessment, Health Care
  • Research Design
  • Research*
  • Risk Factors
  • Schizophrenia / diagnosis
  • Schizophrenia / genetics
  • Schizophrenia / prevention & control*
  • Schizophrenic Psychology*
  • Schizotypal Personality Disorder / diagnosis*
  • Schizotypal Personality Disorder / psychology
  • Schizotypal Personality Disorder / therapy