Estimating first episode psychosis (FEP) incidence rates using U.S. claims data: a need for standardization

This brief’s objective was to examine variation in first-episode psychosis (FEP) incidence rates by applying previously published study criteria to U.S. MarketScan claims data. Estimated FEP incidence rates ranged from 20 to 163 per 100,000 individuals, highlighting the need for standardization. Factors contributing to this variation included ICD coding definitions, age range, duration of continuous enrollment prior to the index diagnosis, minimum number of psychosis-related claims, and antipsychotic prescription requirements.