Intellectual Functioning of Individuals with Mental Disorders on Wechsler Adult Intelligence Scale –Revised (WAIS –R)

The purpose of present research was to evaluate the intellectual functioning of individuals suffering from MajorDepressive Disorder, Obsessive Compulsive disorder and Schizophrenia. After detailed literature review it washypothesized that the mean full scale IQ score of adults with Obsessive Compulsive disorder will be higher thanthe mean full-scale IQ score of adults with (i) Schizophrenia and (ii) Depression. Since the previous centuryresearch work has been started on intelligence investigating how it is related to psychiatric disorders e.g Goodmanand 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; consideringthe independent group design, a sample of 90 (30 in each group) was selected from different psychiatric clinics andhospitals of Karachi- Pakistan. The age range was from 16 to 50 years (mean age=31.5 years).Their educationlevel was Intermediate to Masters. After taking the consent from the authorities their diagnoses were taken fromthe concerned files. The Wechsler Adult Intelligence Scale (WAIS-R, Wechsler, 1981) was administered to assessthe intellectual functioning of the patients, followed by Intake card and Case History Sheet of Institute of ClinicalPsychology, University of Karachi. In order to interpret the results in statistical terminology t-test and ANOVAwere computed. It was indicated that there is a significant difference between mean Full scale IQ scores of adultswith Obsessive compulsive disorder (OCD) and schizophrenia. However an insignificant difference was foundbetween mean full scale IQ scores of adults with Major Depressive disorder and Obsessive compulsive disorder(OCD).Implication of the findings have also discussed.