Evidence of Effectiveness

The Incredible Years program was selected as a "Model" Strengthening Families program by the Center for Substance Abuse Prevention (CSAP), as an "exemplary" program by the Office of Juvenile Justice Delinquency Prevention (OJJDP) and as a "Blueprints" program by OJJDP. The programs have also been recommended by the Home Office in UK as one of the evidenced-based interventions for antisocial behavior and by Sure Start as a recommended program for families with children under five years. As such, the series has been subject to quality reviews by independent groups of scientists, evidenced excellent effectiveness in multiple randomized control group studies, and attained high overall consumer satisfaction ratings.

Please Note: If you are planning to use any of the Incredible Years programs as part of a research grant we strongly recommend your leaders become certified as group leaders and that one of our certified trainers is involved in training your staff and providing ongoing consultation. We ask that you let us know about research projects and send us copies of the research results.

Evidence of Effectiveness:

Six randomized control group evaluations of the parenting series by the program developer and colleagues at the University of Washington as well as five independent replications by other investigators has indicated significant:

• Increases in parent positive affect such as praise and reduced use of criticism and negative commands.

• Increases in parent use of effective limit-setting by replacing spanking and harsh discipline with non-violent discipline techniques and increased monitoring of children.

• Reductions in parental depression and increases in parental self-confidence. 

• Increases in positive family communication and problem-solving.

• Reduced conduct problems in children�s interactions with parents and increases in their positive affect and compliance to parental commands.

Two randomized control group evaluations of the teacher training series  by the program developer and colleagues at the University of Washington

• Increases in teacher use of praise and encouragement and reduced use of criticism and harsh discipline.

• Increases in children's positive affect and cooperation with teachers, positive interactions with peers, school readiness and engagement with school activities. 

• Reductions in peer aggression in the classroom.

Two randomized control group evaluations of the child training series indicated significant:

• Increases in children's appropriate cognitive problem-solving strategies and more prosocial conflict management strategies with peers.

• Reductions in conduct problems at home and school.

See Figure 1 - Comparative Graphs (PDF)

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