Factor Structure and Validity of a Revised Pain Anxiety Symptom Scale

Abstract

The Pain Anxiety Symptoms Scale (PASS) (McCracken et al., 1992) is a frequently used 40-item measure designed to assess fearful appraisals of pain, pain-related cognitive and physiological anxiety, and escape/avoidance behavior. Research has shown the PASS to possess a reasonable validity; however, recent evidence has raised questions regarding the factorial validity of its subscales and indicates that revision and expansion appear warranted. Accordingly, we developed a revised and expanded Pain Anxiety Symptoms Scale (PASS-R). In Study 1, we expanded the item pool and administered the questions to a sample of 69 university students. On the basis of expert opinion and item analysis, we retained a total of 72 items. In Study 2, we subjected the responses of 256 university students to the 72-item PASS-R to a principal-components analysis with oblique rotation. This analysis revealed five lower-order factors (Interference, Approach Behaviours, Catastrophic Thoughts, Monitoring and Prevention, and Physiological Arousal) that loaded together on a single higher-order factor. We created new subscales on the basis of the lower-order factor structure and compared these subscales to a number of other self-report measures of pain, pain behavior, and related psychopathology. The PASS-R subscales demonstrated a good to excellent internal consistency as well as a good construct and criterion validity and contributed unique variance to the prediction of behavioral reactions to recent pain experiences (e.g., visiting a physician). Collectively, these results suggest that the PASS-R is a psychometrically sound self-report measure that allows detailed assessment of anxiety-related cognitions, physiological arousal, and behaviors in response to pain. The paper concludes with a discussion of implications of the studies and future research directions.