Achenbach Teacher’s Report Form (TRF) (28) was used as the primary outcome measure. TRF is widely used in clinical and research settings and has excellent psychometric properties (29). Scores derived from the TRF include the aggression (e.g., “gets in many fights”), rule breaking (e.g., “truancy”; “steals outside the home”), and inattention (e.g., “can’t concentrate”) subscale scores. TRF raw scores are converted to t scores normed by age and sex, and the published norms have been validated for use in children of various ethnicities. Scores on these measures were significantly intercorrelated with correlations ranging from .59 to .67. The proportion of children above the clinical range (a score > 63) on the aggression, rule breaking, and inattention subscales were 36%, 32%, and 30%, respectively.
