Accuracy of self-reported premorbid functioning in schizophrenia

Information on premorbid functioning is often based on patients recalling their past. Premorbid functioning is relevant as it is associated with treatment response and other outcomes. The extent to which memory impairments of persons with schizophrenia may bias such reporting has not been investigated. The purpose of the current study was to assess the extent to which persons with schizophrenia might exhibit biased reporting relative to controls.

Seventy males with schizophrenia or schizoaffective disorder and 51 males with no psychiatric symptoms participated in the study. Contemporaneous and retrospective reports from a behavioral functioning assessment conducted as part of the Israeli Draft Board were compared. This assessment routinely administered to all 17 years old males in the country assesses social functioning, individual autonomy, organizational ability, physical activity and functioning in structured environments. We compared the groups on the Draft Board behavioral measures at age 17 and at re-assessment. We also examined the relationship between symptom severity, neuropsychological performance and differences between age 17 and current behavioral assessment scores.

In a repeated measures MANCOVA of the five measures there was no overall significant difference in accuracy of reporting between persons with schizophrenia and those without. Both groups showed a slight tendency to glorify their past. Consistency of reporting was not significantly correlated with neuropsychological performance or levels of psychotic symptoms.

We found that when reporting on personal and social functioning during teen age years persons with schizophrenia report with the same level of consistency as persons without schizophrenia. This suggests that self-report of premorbid functioning of persons with schizophrenia can be trusted as being reasonably accurate.