background There is little research on characteristics and prognosis of early onset psychosis (at the age of 12-18 years).

aim To advance our knowledge of this disorder for the purpose of proper diagnosis and treatment. Premorbid and prodromal characteristics, treatment history, symptoms and classifications, and similarities and differences between subgroups with affective and with schizophrenic psychosis are focused on.

method A chart review was constructed to study a group of 129 subjects with psychotic symptoms.

results The group was characterised by early - but non-specific - treatment, developmental problems (mostly social), and clear prodromes. Drug abuse, depressive symptoms and suicidal behaviour were also frequent. Male gender, a relatively long prodromal phase, school problems and drug abuse were more indicative for a schizophrenic subgroup. Introversion was characteristic for schizophrenic boys. Classificaties, however, were not stable.

conclusions These findings suggest that early identification of all early onset psychosis should take place in existing treatment settings. Careful examination of the prodromal phase seems helpful to differentiate between schizophrenic and affective psychosis, which is significant for both research as (early) intervention.