The Psychometric Properties of the Behavioral Inhibition System (BIS) and Behavioral Activation System (BAS) scales Among Students of Shiraz University

The Behavioral Inhibition System(BIS) and Behavioral Activation System(BAS) Scales(BIS/BASS) were developed by Carver and White(1) as self-report measures derived from the two behavioral systems in Gray's theory(2,3). The purpose of the present study was to examine carry out Carver and White’s model with Shiraz university students. In order to this research, exploratory factor structure of the BIS/BASS was used. These scales were administrated to a sample of 188 students of Shiraz university. The reliability coefficients was estimated by two test retest and Cronbach's alpha, which were both acceptable. Factor analysis was showed for 4 factors labeled as: Inhibition (BIS), Drive (BASD), Reward (BASR) and Fun seeking (BASF) which covered 47.98 percent of the total variance. The validity of these scales was investigated in two different ways: convergent validity and divergent validity. These validity indices were measured by two subscales of depression and anxiety from SCL-90-R. The correlation coefficient of subscale of BIS for depression was 0.22 while BIS for anxiety was 0.31. Thus, Carver and White’s model was normalized with the Iranians.