The validity of diagnoses of non-affective psychotic disorder including schizophrenia in Swedish registers revisited – are the diagnoses valid for migrants and Swedish-born?

This study supports continued use of the register-diagnoses but only after taking appropriate measures to avoid that patients with additional psychotic disorder due to psychoactive substance are not violating the validity. It also suggests caution when studying non-affective psychosis diagnoses among migrant women as the validity is low, possibly due to difficulties in separating non-affective psychosis from symptoms of other disorders with psychotic features.