Am J Psychiatry 1993; 150:880-884
Copyright © 1993 by American Psychiatric Association
The reliability of three definitions of bizarre delusions
RL Spitzer, MB First, KS Kendler and DJ Stein
Department of Psychiatry, Columbia University College of Physicians and Surgeons, New York, NY.
OBJECTIVE: This study was conducted to determine whether the interjudge
reliability of the DSM-III-R concept of bizarre delusions could be improved
by alternative definitions of the concept. METHOD: Twelve raters evaluated
180 delusions of separate psychiatric patients according to the DSM-III-R
and two alternative definitions of bizarre delusions. RESULTS: The kappas
for the DSM-III-R definition and for one of the alternative definitions
were 0.64 and 0.65, respectively; for the other alternative definition it
was 0.45. All three definitions were highly intercorrelated, largely
identifying the same cases. CONCLUSIONS: Neither of the alternative
definitions of bizarre delusions was more reliable than the DSM-III-R
definition. The reliability of the DSM-III-R definition, although only
fair, is comparable to that of other important clinical concepts that play
a major role in the DSM-III-R diagnostic criteria for psychotic disorders.
