Measurement of social introversion by the MMPI-2

Psychometric characteristics of the Social Introversion (Si) scale, the Social Discomfort (SOD) scale, and the Si subscales of the MMPI-2 were examined in clinical samples of 122 psychiatric patients and 399 patients with substance-use disorders. The combined Si1 (Shyness/Self-Consciousness) and Si2 (Social Avoidance) subscales correlated highly with SOD and are apparent measures of the social introversion construct. Si3 (Self/Other Alienation) was found to be a measure of the general maladjustment factor of the MMPI-2. Content not included on the Si subscales was divided into a group of items that measures general maladjustment and 2 other item groups that may assess minor constructs related to social introversion. As in previous research, the 3 Si subscales accounted well for variance in Si scores.