Psychological inflexibility in childhood and adolescence: Development and evaluation of the Avoidance and Fusion Questionnaire for Youth.

The authors describe the development and validation of the Avoidance and Fusion Questionnaire for Youth (AFQ-Y), a child-report measure of psychological inflexibility engendered by high levels of cognitive fusion and experiential avoidance. Consistent with the theory underlying acceptance and commitment therapy (ACT), items converged into a 17-item scale (AFQ-Y) and an 8-item short form (AFQ-Y8). A multimethod psychometric approach provides...