Effects of the incredible years parenting program on children's interpersonal conflict: An integrative data analysis.

Behavioral parenting programs, such as Incredible Years (IY), reduce conduct problems in children. However, conduct problems encompass many different behaviors, and little is known about the effects of parenting programs on specific aspects of children's conduct problems, such as children's relationships with others. The aim of this study was to examine, for the first time, the effects of the IY parenting program on children's levels of conflict with their parents, siblings, and peers. We used individual participant-level data pooled across 12 randomized trials in Europe, comprising a total of 1,409 families: child aged 1-11 years ( = 5.53 years, = 1.56) and 61% male, 60% low-income families, and 30% from an ethnic minority. Multilevel models were used to explore the effects of IY on children's conflict with parents, siblings, and peers. The IY program reduced children's conflict with their parents (β = -.21), but there were no main effects of the program on conflict with siblings or peers. Moderation analyses showed that IY reduced conflict in sibling relationships for the 22% of families with the most severe sibling conflict at baseline. This suggests that high-quality behavioral parenting programs, such as IY, can effectively reduce children's conflict within the home (i.e., with parents and siblings), especially when initial levels of sibling conflict are high, but do not have broader benefits on children's interpersonal conflict outside of the home (i.e., with peers). (PsycInfo Database Record (c) 2024 APA, all rights reserved).