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Incredible Years Parent Training: What Changes, for Whom, How, for How Long?

NCJ Number
Journal of Applied Developmental Psychology Volume: 44 Dated: 2016 Pages: 93-104
Date Published
12 pages

The authors report on a study to examine the impacts of the Incredible Years program with families of preschoolers; they present their research methodology and outcomes.


The aims of this study were to examine the efficacy of the Incredible Years program (IY) with Portuguese families of preschoolers, moderator and mediator effects, and sustainability of results. Research design involved a randomized controlled design with pre- and post-intervention, and follow-up assessments at 12- and 18-months post-intervention. Participants included 124 children, aged three to six years, who were at risk of disruptive behavior problems. Children in the IY group showed significant reduction in behavior problems and increase in social skills; caregivers improved parenting practices and self-confidence. Positive clinical and functional impacts were demonstrated. IY was efficacious with a wide range of families. The moderating effect of the child's age suggests that IY prevents a decrease in social skills for the ages covered by this study. Changes in parental self-efficacy affected changes in parental practices, promoting changes in children's behavior. Positive effects were maintained over time. Publisher Abstract Provided

Date Published: January 1, 2016