The Children's Headache Assessment Scale (CHAS): factor structure and psychometric properties.

This study investigated the content validity, factor structure, and psychometric properties of the Children's Headache Assessment Scale (CHAS), a parent rating scale for identifying environmental variables associated with pediatric headache. In Study 1, input from physicians and psychologists was obtained to develop a revised set of 44 items receiving high endorsement. In Study 2, the questionnaire was administered to parents of 92 child headache sufferers, ages 6-16, and readministered 2 weeks later. An exploratory factor analysis revealed five factors (Disruptive Impact, Social Consequences, Stress Antecedents, Physical Antecedents and Quiet Coping, and Prescription Medication Use) that reflect distinct environmental concomitants of childhood headache. Scale reliabilities (alpha, .64-.82) indicate acceptable internal consistency, and test-retest reliabilities indicate relatively stable factors and items. High scores on the Disruptive Impact factor were associated with more severe, lengthy, and infrequent headache occurrence, lending initial support for the validity of this factor. Overall, the findings support the clinical and research utility of the CHAS in behavioral treatment of childhood headache.