Obsessive-compulsive (OC) symptoms have been observed in a substantial prop
ortion of schizophrenic patients. In this study, we assessed the rate of oc
currence of OC symptoms and the interrelationship between OC and schizophre
nic symptoms in 68 hospitalized chronic schizophrenic patients. The patient
s were interviewed with the Structured Clinical Interview fur Axis-I DSM-IV
Disorders - Patient Edition (SCID-P) and the appropriate rating scales inc
luding the Scale for the Assessment of Positive Symptoms, the Scale for the
Assessment of Negative Symptoms, the Yale-Brown Obsessive-Compulsive Scale
(Y-BOCS), the Barnes Akathisia Scale, the Abnormal Involuntary Movement Sc
ale, and the Social Behaviour Schedule (SBS), Sixteen patients (23.5%) met
the DSM-IV criteria for OCD. A comparison of schizophrenic patients with an
d without OCD showed that the schizo-obsessive patients were significantly
(1.7-fold) more impaired in basic social functioning, as reflected by the S
BS score. No significant between-group differences for any of the other cli
nical variables were found. There was no significant correlation between OC
and schizophrenic symptoms within the schizo-obsessive subgroup. The mean
Y-BOCS score for the patients with both schizophrenia and OCD was within th
e typical range (22.8 +/- 1.7) observed in OCD without psychosis. The findi
ngs provide further evidence for the importance of the OC dimension in schi
zophrenia and may have important implications for the application of effect
ive treatment approaches in this difficult-to-treat subgroup of schizophren
ic patients. (C) 2001 Elsevier Science Ireland Ltd. All rights reserved.