IRT-based Self-report Screener for Prodromal Schizophrenia and Early Psychosis

DESCRIPTION (provided by applicant): Schizophrenia is one of the most debilitating and costly mental illnesses in the United States, with peak incidence in individuals aged 14-25 and causing annual direct and indirect costs of over 62.7 billion (Wu et al., 2005). Several studies suggest that early identification and treatment can delay onset and decrease the severity of schizophrenia, leading to a significant reduction in the irreversible neuroanatomical changes and cognitive deficits often associated withthe onset of schizophrenia (McGlashan et al, 2006; Piontkewitz, et al, 2009; Simon et al., 2007). The critical barrier to advances in prodromal and early psychosis (PEP) research and treatment has been the identification of PEP individuals who are at riskof conversion to a psychotic disorder. Clinician-administered PEP screening assessments are time-consuming and costly, both in terms of required expertise and administration time (Lindenmayer et al, 2007). The proposed project will facilitate PEP screening and clinical research recruitment with the development of brief paper and computerized self-report PEP assessments that are appropriate for public sector mental health outpatients, 14-25 years of age. To accomplish this, we will utilize state-of-the artself- report item development methodology that is novel to PEP research, namely cognitive interviewing (CI) with 50 PEP outpatients as well as item response theory (IRT) analysis of responses from 1000 outpatients with varying levels of severity, includingno symptoms, PEP, and a psychotic disorder. These methods will reduce population-specific biases and increase measurement precision and thereby, predictive validity. We will establish the convergent and predictive validit of our assessments against the SIPS and 12-month SCID-based diagnostic outcomes, respectively, as well as the predictive validity of the PQ-92 against the same outcomes. Computerized versions of the new PEP screeners will permit rapid scoring, clinical and research report generation, andfollow-up with a computerized structured diagnostic assessment, the NetSCID, when integrated into our existing secure diagnostic Web portal. We have partnered with highly skilled consultants including three NIMH North American Prodrome Longitudinal Study (NAPLS) PIs, two PIs from the NIMH Recovery After an Initial Schizophrenia Episode (RAISE) clinical trial, a researcher representing the foremost ultra-high risk (UHR) research center outside the U.S., and a quantitative expert in IRT. This project is likely to have a substantial impact on the identification and treatment of PEP. It will facilitate PEP research by increasing the predictive validity of self-report screening thereby improving clinical trial recruitment. Routine screening of outpatients with our instruments may enable a greater number of PEP individuals to gain access to NAPLS-validated interventions, which may delay or prevent onset of a psychotic disorder; thereby serving to improve the lives of people suffering from psychosis and their families; prominent components of NIMH's overall mission. PUBLIC HEALTH RELEVANCE: Once developed, the proposed prodromal and early psychosis (PEP) assessments (the PEPS and PEPSS) will give researchers and clinicians the potential to use a multidimensional self-report instrument to identify individuals at risk of converting to a psychotic disorder; thereby, facilitating screening and clinical research recruitment of PEP outpatients who may benefit from further evaluation and possible inclusion in a validated PEP treatment intervention. As such, this project is likely to have a substantial impact on the identification, treatment, and possible prevention of psychosis as well as the lives of individuals at-risk for and suffering from psychotic disorders andtheir families; two prominent components of NIMH's overall mission.