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BACKGROUND: There is abundant evidence that schizophrenia is associated with cognitive deficits in childhood. However, previous studies investigating school performance have been inconclusive. Furthermore, there are several biological and social factors that could confound the association. We investigated whether school performance at age 16 is associated with risk of adult schizophrenia and other psychoses in a large national cohort, while controlling for multiple confounders.MethodUsing a national sample of 907 011 individuals born in Sweden between 1973 and 1983, we used Cox regression to assess whether scholastic achievement at age 15-16 predicted hospital admission for psychosis between ages 17 and 31, adjusting for potential confounders. RESULTS: Poor school performance was associated with increased rates of schizophrenia [hazard ratio (HR) 3.9, 95% confidence interval (CI) 2.8-5.3], schizo-affective disorder (HR 4.2, 95% CI 1.9-9.1) and other psychoses (HR 3.0, 95% CI 2.3-4.0). Receiving the lowest (E) grade was significantly associated with risk for schizophrenia and other psychoses in every school subject. There was no evidence of confounding by migrant status, low birthweight, hypoxia, parental education level or socio-economic group. CONCLUSIONS: Poor school performance across all domains is strongly associated with risk for schizophrenia and other psychoses. [ABSTRACT FROM AUTHOR]

Objective. To investigate the specificity of the 'jump-to-conclusions' (JTC) bias in delusions.Methods. Thirty-seven psychotic patients were divided into two separate groupings: (I) deluded versus non-deluded individuals and (2) individuals with and without a diagnosis of schizophrenia. Groups were compared on three reasoning tasks ('Beads' task, Wason's 2-4-6 task, and Wason's selection task).Results. Deluded participants had a tendency to show a JTC bias on data-gathering tasks, but no differences were found with the schizophrenia diagnosis grouping. There were no differences between any groups on tasks of general reasoning and probability judgments.Conclusion. The results suggest that JTC is specific to delusions rather than diagnosis, and to data gathering rather than a general deficit in reasoning. [ABSTRACT FROM AUTHOR]

Background. Saccadic distractibility, as measured by the antisaccade task, has attracted attention as a putative endophenotypic marker for schizophrenia. Some studies have suggested that this measure is elevated in the unaffected relatives of schizophrenia patients. However, recent studies have called this into question and the topic remains controversial.Method. Saccadic distractibility was measured in 53 patients with DSM-IV schizophrenia, 80 unaffected first-degree relatives and 41 unaffected controls.Results. Schizophrenia patients performed worse than relatives and controls combined (p<0·00001), but relatives did not differ significantly from controls. Performance in multiply affected families was no worse than that in singly affected families. Relatives with a high presumed genetic risk for schizophrenia performed no worse than other relatives. The performance of the patients did not predict that of their relatives.Conclusions. These results demonstrate that saccadic distractibility is strongly associated with disease status but not with genetic loading for schizophrenia. We conclude that saccadic distractibility is unlikely to be useful as an endophenotypic marker in schizophrenia. [ABSTRACT FROM AUTHOR]