Background The absence of systematic screening for psychosis within general psychiatric services contribute to substantial treatment delays and poor long-term outcomes. We conducted a meta-analysis to estimate rates of psychotic experiences, clinical high-risk for psychosis syndrome (CHR-P), and psychotic disorders identified by screening treatment-seeking individuals to inform implementation recommendations for routine psychosis screening in general psychiatric settings.

Methods PubMed and Web of Science databases were searched to identify empirical studies that contained information on the point prevalence of psychotic experiences, CHR-P, or psychotic disorders identified by screening inpatient and outpatient samples aged 12-64 receiving general psychiatric care. Psychotic experiences were identified by meeting threshold scores on validated self-reported questionnaires, and psychotic disorders and CHR-P by gold-standard structured interview assessments. A meta-analysis of each outcome was conducted using the Restricted Maximum Likelihood Estimator method of estimating effect sizes in a random effects model.

Results 41 independent samples (k=36 outpatient) involving n=25,751 patients (58% female, mean age: 24.1 years) were included. Among a general psychiatric population, prevalence of psychotic experiences was 44.3% (95% CI: 35.8-52.8%; 28 samples, n=21,957); CHR-P was 26.4% (95% CI: 20.0-32.7%; 28 samples, n=14,395); and psychotic disorders was 6.6% (95% CI: 3.3-9.8%; 32 samples, n=20,371).

Conclusions High rates of psychotic spectrum illness in general psychiatric settings underscore need for secondary prevention with psychosis screening. These base rates can be used to plan training and resources required to conduct assessments for early detection, as well as build capacity in interventions for CHR-P and early psychosis in non-specialty mental health settings.

The authors have declared no competing interest.

The authors report no conflicts of interest. Dr. Clauss was supported by the Dupont Warren Fellowship of Harvard Psychiatry, Louis V. Gerstner Scholar Award, and the Chen Institute Mass General Neuroscience Transformative Scholar Award. Dr. Foo was supported by funding from the Massachusetts Department of Mental Health to the Massachusetts General Hospital Center of Excellence for Psychosocial and Systemic Research, Sidney R. Baer, Jr Foundation, and the National Institute of Mental Health (P50 MH115846-05). Catherine Leonard was supported by funding from the Massachusetts Department of Mental Health to the Massachusetts General Hospital Center of Excellence for Psychosocial and Systemic Research. Dr. Cather was supported by funding from the Massachusetts Department of Mental Health to the Massachusetts General Hospital Center of Excellence for Psychosocial and Systemic Research. Dr. Holt was supported by funding from the National Institute of Mental Health (R01MG127265; R01MH125426; and R01MH122371-SCH), the Massachusetts Department of Mental Health, and the Sidney R. Baer, Jr Foundation.

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