We fit the three-level growth curve model to capture children’s behavior outcome changes over time in three growth parameters (intercept, time slope and quadratic term). Parent and teacher outcomes were examined in separate models. The variation in the growth parameters was partitioned into (a) the variation among children within intervention unit was captured in the level-2 model, and (b) the variation among intervention units is represented in the level-3 model. Equations for the models are available online.
