A three-level growth curve model was constructed by using HLM 7.0 with full maximum likelihood (FML) estimation method (Raudenbush & Bryk, 2002). The model included three levels: (a) times of measurement, (b) nested within children, and (c) nested within the intervention units (with each group having a consistent group leader). For the teacher-rated BASC, 3 participants had missing data at pre-intervention, 26 at post-intervention, and 50 at the one-year follow-up. For the parent-rated BASC, 14 participants had missing data at post-intervention, and 24 at the one-year follow-up. Five participants withdrew from the study before the one-year follow-up.
