Examining the Impact of the Incredible Years Parenting Program: A Systematic Review of Randomized Controlled Trials in Early Childhood

Year 2025, Volume: 5 Issue: 1, 45 - 61, 30.06.2025

Nilüfer Kuru

Abstract

The Incredible Years (IY) parenting program is an intervention that has been widely implemented to improve parenting practices and child development. This systematic review examined randomized controlled trials (RCTs) that assessed the effectiveness of IY programs for children aged 0–8 and their caregivers. A comprehensive literature search was conducted in the Web of Science, PsycINFO, and ERIC databases for studies published between 2021 and 2025. Inclusion criteria required an RCT design and implementation of the IY parenting program with parents of children under eight. The review followed PRISMA guidelines. Eleven eligible studies were included. The findings showed consistent reductions in children's externalizing behaviors and improvements in parenting strategies. Several studies also reported positive changes in children’s emotional regulation, developmental outcomes, and caregivers' psychological well-being. Some trials examined biological indicators, such as DNA methylation, which suggests preliminary evidence of physiological benefits. However, effects based on teacher reports and observational tools were less consistent. The Incredible Years program appears to be an effective intervention for enhancing behavioral and developmental outcomes in children and improving parental well-being. It is a promising intervention for promoting early childhood mental health, though further research is needed on its long-term and biological impacts

Keywords

Incredible Years, parenting program, early childhood, randomized controlled trial, psychosocial outcomes

Ethical Statement

İlgili araştırmada anket, mülakat, odak grup çalışması, gözlem, deney, görüşme teknikleri kullanılarak katılımcılardan veri toplanmasını gerektiren araştırma türü olmadığından ve doküman incelemesi yoluyla yürütüldüğü için etik kurul iznine tabi değildir. Ayrıca araştırmanın tüm sürecinde Committee on Publication Ethics (COPE) tarafından belirlenen etik kurallara uyulmuştur.

Eşsiz Yıllar Ebeveynlik Programının Etkililiğinin İncelenmesi: Erken Çocuklukta Yürütülen Randomize Kontrollü Çalışmaların Sistematik Derlemesi

Abstract

The Incredible Years (IY) parenting program is an intervention that has been widely implemented to improve parenting practices and child development. This systematic review examined randomized controlled trials (RCTs) that assessed the effectiveness of IY programs for children aged 0–8 and their caregivers. A comprehensive literature search was conducted in the Web of Science, PsycINFO, and ERIC databases for studies published between 2021 and 2025. Inclusion criteria required an RCT design and implementation of the IY parenting program with parents of children under eight. The review followed PRISMA guidelines. Eleven eligible studies were included. The findings showed consistent reductions in children's externalizing behaviors and improvements in parenting strategies. Several studies also reported positive changes in children’s emotional regulation, developmental outcomes, and caregivers' psychological well-being. Some trials examined biological indicators, such as DNA methylation, which suggests preliminary evidence of physiological benefits. However, effects based on teacher reports and observational tools were less consistent. The Incredible Years program appears to be an effective intervention for enhancing behavioral and developmental outcomes in children and improving parental well-being. It is a promising intervention for promoting early childhood mental health, though further research is needed on its long-term and biological impacts

Keywords

Eşsiz yıllar, ebeveynlik programı, erken çocukluk, randomize kontrollü deneysel desen, psikososyal sonuçlar

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