Am J Psychiatry 1992; 149:494-499
Copyright © 1992 by American Psychiatric Association
Bizarre delusions and DSM-III-R schizophrenia
D Goldman, DA Hien, GL Haas, JA Sweeney and AJ Frances
Department of Psychiatry, Western Psychiatric Institute and Clinic, Pittsburgh, PA 15213.
OBJECTIVE: Bizarre delusions are assigned greater weight relative to other
delusions in the DSM-III-R diagnosis of schizophrenia. The decision to
emphasize bizarre delusions was based largely on historical tradition
rather than empirical evidence. This study examined 1) the extent to which
a history of bizarre delusions contributes to the diagnosis of
schizophrenia and 2) whether schizophrenic patients with bizarre delusions
constitute a clinically distinguishable subgroup. METHOD: Two hundred
fourteen consecutively admitted psychotic inpatients were assessed for
bizarre delusions according to the DSM-III- R criteria. Clinical and
demographic correlates of bizarre delusions were examined in subsets of
patients diagnosed as schizophrenic according to DSM-III-R who also
received CT scans and neuropsychological testing. RESULTS: With the base
prevalence rate for schizophrenia of 0.71, bizarre delusions had a
sensitivity of 0.79, a specificity of 0.56, and a positive predictive power
of 0.82 for the diagnosis of schizophrenia (N = 152) relative to other
psychotic disorders (N = 62). Clinical, neurobehavioral, CT scan, and
premorbid adjustment data on the schizophrenic patients indicated that
beyond manifesting more severe positive symptoms, patients with bizarre
delusions did not otherwise constitute a clinically distinguishable
subgroup. CONCLUSIONS: The data suggest that criterion A for the diagnosis
of schizophrenia in DSM-IV could be improved by removing the special
emphasis that was placed on bizarre delusions in DSM-III-R.
