The Patient-Reported Outcomes Measurement Information System (PROMIS) pediatric and parent-proxy short forms for anxiety: Psychometric properties in the Kids FACE FEARS sample.

There is tremendous need for brief and supported, non-commercial youth- and caregiver-report questionnaires of youth anxiety. The pediatric and parent proxy short forms of the Patient-Reported Outcomes Measurement Information System (PROMIS) Anxiety scale (8a v2.0) are free, brief, publicly accessible measures of youth- and caregiver-reported anxiety in children and adolescents. Despite increased use of the PROMIS, no study has evaluated performance of its anxiety scales in a sample of treatment-engaged anxious youth. Analyses were conducted on baseline data from the first 265 families (child MAge=11.14 years, 70% racial/ethnic minoritized youth) to enroll in the Kids FACE FEARS trial, a multisite comparative effectiveness trial of therapist-led vs. self-administered treatment for elevated youth anxiety. Confirmatory factor analysis (CFA) examined factor structure; omega coefficients and regression models examined internal consistency, convergent validity, and cross-informant reliability. CFA supported adjusted single-factor solutions across youth and caregiver reports, and internal consistency was high. Convergent validity was supported by medium-to-large associations with anxiety-related impairment and severity. Moderate cross-informant reliability between reports was found. Results showcase the first psychometric study of the PROMIS Anxiety scale short forms among treatment-engaged youth with elevated anxiety. Findings highlight the PROMIS Anxiety scale's utility in typical care settings for youth anxiety.