Abstract
Background: Early identification of people developing psychosis is now a goal of all psychiatric services to reduce the delay for treatment and support. The neurodevelopmental model of schizophrenia predicts cognitive limitations and decline before the onset of the first episode which may be a factor in early identification.
Aims: This study aims to evaluate cognitive decline prior to the first episode using school performance data.
Method: Ninety-nine school reports of the first and last class in secondary education are compared for 33 probands, 33 of their siblings and 33 normal control subjects who were matched for academic level according to Dutch school types.
Results: The findings indicate that probands performed at a lower level than siblings and normal controls after transfer to secondary education and on leaving but there was no expected progressive performance decline over this period.
Conclusion: The findings support the neurodevelopmental view that people who develop schizophrenia experience delays in development that are apparent in school performance at age 13. Serious cognitive decline probably occurs quite rapidly just before the frank expression of psychotic symptoms.
Declaration of interest: None.