Evolution of first episode psychosis diagnoses and health service use among young Māori and non-Māori-A New Zealand national cohort study.

Indigenous differences in schizophrenia and affective psychosis diagnoses could be related to differential exposure to socio-environmental risk or assessor bias. The lower rate of co-morbid affective and anxiety disorders indicates a potential under-appreciation of affective symptoms in Māori youth with first episode psychosis.