The First Step to Success Program: An Analysis of Outcomes with Identical Twins across Multiple Baselines

The investigation described here focused on effects of the First Step to Success early intervention program designed for kindergartners who show the early signs of emerging antisocial behavior at the point of school entry. First Step is a collaborative home and school intervention that was developed to address the needs of such children and was evaluated over a 4-year period. Two studies are reported herein, involving two sets of identical twins enrolled in regular kindergarten programs. The results of these studies indicated that exposure to the First Step program produced powerful behavior changes that were maintained throughout the program's duration. Limitations of the studies are discussed, as well as questions for future research.