چکیده (انگلیسی):

The purpose of present research was to evaluate the intellectual functioning of individuals suffering from Major
Depressive Disorder, Obsessive Compulsive disorder and Schizophrenia. After detailed literature review it was
hypothesized that the mean full scale IQ score of adults with Obsessive Compulsive disorder will be higher than
the mean full-scale IQ score of adults with (i) Schizophrenia and (ii) Depression. Since the previous century
research work has been started on intelligence investigating how it is related to psychiatric disorders e.g Goodman
and Graham, (1996) found psychiatric problems as the strongest consistent predictor of intelligence quotient (IQ).
Further several other researchers found the effects of psychological disorders on intellectual functions (Tallis et al.
1999; Savage et al. 2000; Zitterl et al, 2001; Tuna et al. 2005). Through purposive sampling technique; considering
the independent group design, a sample of 90 (30 in each group) was selected from different psychiatric clinics and
hospitals of Karachi- Pakistan. The age range was from 16 to 50 years (mean age=31.5 years).Their education
level was Intermediate to Masters. After taking the consent from the authorities their diagnoses were taken from
the concerned files. The Wechsler Adult Intelligence Scale (WAIS-R, Wechsler, 1981) was administered to assess
the intellectual functioning of the patients, followed by Intake card and Case History Sheet of Institute of Clinical
Psychology, University of Karachi. In order to interpret the results in statistical terminology t-test and ANOVA
were computed. It was indicated that there is a significant difference between mean Full scale IQ scores of adults
with Obsessive compulsive disorder (OCD) and schizophrenia. However an insignificant difference was found
between mean full scale IQ scores of adults with Major Depressive disorder and Obsessive compulsive disorder
(OCD).Implication of the findings have also discussed.