Universal Teacher-Child Interaction Training in early childhood special education: Identifying mechanisms of action that explain why it works.

Teacher-Child Interaction Training-Universal (TCIT-U) is effective for increasing teachers' use of strategies that promote positive child behavior; however, the exact mechanisms of change are unknown. Using a cluster randomized control trial in a sample of 410 racially- and ethnically-diverse children (M = 41.73 months; 50% White, 45% Black/African-American, 4% Multiracial, 1% Asian; 59% Hispanic; 87% with disabilities) taught by 102 teachers from 38 classrooms in eight schools, we attempted to identify these mechanisms of action.