Cumulative risk predicting differential effectiveness of the incredible years parent-training

The evidence on whether socioeconomic status moderates the effectiveness of parent-training programs for disruptive child behaviors is inconclusive. These varied results may stem from differences in the programs or the studies themselves. We applied an equivalence test paradigm to test the hypothesis of equal benefit from the Incredible Years Parent-Training (IYPT) across family risk on disruptive child behaviors. During the Danish roll-out of the IYPT, 1203 families were recruited across 20 different municipalities. The isolated and cumulative effect of five markers of low socioeconomic status, specifically single parent household, parental unemployment, low family income, low parental educational level, and teen parenthood, were analyzed as predictors of pre-to-post treatment response. Results showed equal benefit among families experiencing from zero to four accumulated socioeconomic risks (99 % of our sample). Our findings suggest that the IYPT brings equal benefit across socioeconomic backgrounds and risk levels in Danish community settings. • Cumulative socioeconomic risk did not predict differential effectiveness of Incredible Years Parent-Training (IYPT). • The IYPT equally benefitted Danish families with up to four out of five socioeconomic risk factors. • Future studies should apply equivalence tests to advance knowledge on equal benefit from parent-training.