Reliability and validity of the Child Pain Anxiety Symptoms Scale (CPASS) in a clinical sample of children and adolescents with acute postsurgical pain

Pain anxiety refers to the cognitive, emotional, physiological, and behavioural reactions to the experience or anticipation of pain. The Child Pain Anxiety Symptoms Scale (CPASS) has recently been developed and validated in a pediatric community sample. The goal of the present study was to examine the psychometric properties of the CPASS in a sample of children and adolescents with acute postsurgical pain. Eightythree children aged 8–18 years (mean 13.8 years, SD 2.4) completed measures of pain anxiety, anxiety sensitivity, pain catastrophizing, anxiety, depression, and pain intensity and unpleasantness 48–72 hours after major surgery; and pain intensity and unpleasantness, pain anxiety, and functional disability approximately 2 weeks after discharge from the hospital. The CPASS showed excellent internal consistency (a = 0.915). Stronger partial correlations of pain anxiety with anxiety sensitivity (r = 0.70) and pain catastrophizing (r = 0.73) compared to pain anxiety with anxiety (r = 0.53) and depression (r = 0.59) suggest excellent construct validity. Pain anxiety was significantly associated with pain intensity (r = 0.44) and unpleasantness (r = 0.32) 48–72 hours after surgery (concurrent validity) and with pain unpleasantness (r = 0.29) and functional disability (r = 0.50; but not pain intensity, r = 0.20) 2 weeks later (predictive validity). The CPASS showed adequate sensitivity to change over time (mean change = 9.52; effect size = 0.49) and good sensitivity and specificity. The results of the present study provide initial validity and reliability of the CPASS in a clinical sample of children and adolescents after major surgery.