Measuring treatment motivation in secure juvenile facilities.

The present study examined the validity and reliability of the Adolescent Treatment Motivation Questionnaire (ATMQ) in a sample of 264 adolescents in Dutch secure juvenile facilities. Confirmatory factor analysis of a single-factor model of "treatment motivation" showed a close fit to the data, indicating construct validity of the ATMQ. Concurrent validity was supported by significant relations between treatment motivation and living group climate. Internal consistency reliability in terms of Cronbach's alpha was good (.84). The ATMQ proved to be insensitive to the tendency to provide socially acceptable or desirable answers, which supports discriminant validity, and was unrelated to sex, age, and self-reported aggression of the adolescents. The ATMQ is a parsimonious instrument (11 items) enabling future research on treatment motivation in secure juvenile facilities.