The long-term impact of investing in early life parenting programmes in Ireland

Introduction

Early childhood is a crucial period for developing the skills needed to succeed in life. Pregnancy and infancy represent the most productive stages for brain development, when core neurodevelopmental capacities are formed (Knudsen et al. 2006; Desrosiers et al. 2024). While genetics play a significant role, epigenetics demonstrates that environmental factors—particularly parental stimulation and sensitive caregiving—profoundly influence brain networks, shaping later cognitive, social, behavioural, and physical development (Shonkoff, 2010; Gee and Cohodes, 2021). As a result, socioeconomic inequalities often emerge in disadvantaged contexts where families face monetary constraints (Becker, 1965) and poverty-related stress (Mani et al. 2013; Masarik and Conger, 2017), which may limit their ability to invest in children’s development. These inequalities arise early and, if unaddressed, may widen through schooling (Cunha and Heckman, 2007; Heckman and Mosso, 2014). Studies demonstrate that almost a half of the income-related gaps in children’s skills can be attributed to differences in parenting style and the home environment (Waldfogel and Washbrook, 2011; Kalil et al., 2016). To reduce these inequalities, intervening early in life to offset these deficits is increasingly recognised as an effective strategy (see OECD, 2016).

While a number of studies have examined the short-term effects of early life parenting programmes, there are relatively few experimental studies, especially for Ireland, that have tested the sustained impact on children’s development into adolescence. This paper addresses this gap by summarising the results from the Age 14 follow-up of Preparing for Life (PFL), a prenatal to age 5 home visiting programme operating in Dublin. Funded by Atlantic Philanthropies and the Irish Government, PFL was developed collaboratively by the Northside Partnership in conjunction with the local community to address inequalities in school readiness skills (Doyle, 2013). The programme is grounded in several psychological theories of development including the theory of human attachment, socio-ecological theory of development, and social-learning theory. PFL differs from other well-known home visiting programmes in terms of length, intensity, and approach. It provides 5 years of multi-treatment supports starting during pregnancy. Although some programmes start in the prenatal period, most start after birth. By intervening during pregnancy and the first few years of life, the programme capitalises on heightened brain malleability. PFL is also longer in duration than most other programmes. This is important for two reasons. First, longer programme duration allows the home visitors to develop and deepen their relationships with families. Second, building on the skills-beget-skills hypothesis (Cunha and Heckman, 2007), intervening from pregnancy until school entry allows the treatment to respond appropriately to the child’s growing skill set. PFL adopts a flexible and strengths-based approach and is grounded in ‘Advantaged Thinking’ – a strengths-based philosophy which prioritises potential, dignity, and ambition within families over deficits.

Previous studies of PFL have identified significant programme effects at age 5 (Doyle, 2020) and age 9 (Doyle, 2024; Coy and Doyle, 2024) in terms of children’s cognitive skills, health, and behavioural development. These effects were larger and more long-lasting than many US-based home visiting programmes (Sweet and Applebaum, 2004; Filene et al., 2013; Peacock et al., 2013; Jeong et al., 2021; Dadisman, Nickow, and Oreopoulos, 2024). The results of the 14-year-old follow-up are the focus of this paper. The results demonstrate sustained programme effects nearly a decade after the intervention ended. Adolescents in the high-treatment group exhibited significantly higher cognitive skills, superior working memory, fewer attention problems, and lower obesity risk relative to the low-treatment group. They also reported stronger parent–child bonds and higher educational aspirations. These findings highlight the long-term benefits of early, intensive, and relationship-based home visiting programmes, reinforcing their role as effective policy tools to reduce inequality and generate lasting societal returns.

Study Design

• Randomised Controlled Trial: This study, which began in 2008, is built on a Randomised Controlled Trial (RCT) design to evaluate the impact of the PFL programme. When the study began, pregnant women living in the target area were invited to participate and were randomly assigned to one of two groups:
  • High-Treatment Group (115 families): Received the full PFL intervention, which included intensive home visits, parenting support, learning resources, and personalised guidance from pregnancy until the child started school. It also included baby massage and group-based parenting classes.
  • Low-Treatment Group (118 families): Received a less intensive version of the programme, serving as an active comparison group.

Figure 1 describes the supports provided to both groups.

Since the groups were randomly assigned, any differences between them can be attributed to the programme’s impact rather than other factors. Thus, at the beginning of the study, the two groups had comparable backgrounds in terms of family income, education, and health.

Figure 1: PFL RCT

• Assessment Components: The study team, based at the UCD Geary Institute for Public Policy, used questionnaires, interviews, and direct assessments to gather the Age 14 data. This included measures of the parent-child relationship, physical health examinations (height, waist measurements, and biological samples), surveys on emotional well-being and future educational aspirations, and tests of cognitive development and executive functioning (such as working memory and problem-solving).
• Sample Retention: In total, 99 of the original 233 participants took part in the Age 14 assessment (high treatment = 45%; low treatment = 40%). Despite the substantial time and effort invested in recruitment efforts, the participation rate was lower than that achieved at Age 9 (50%). A comparison of the baseline characteristics of the high and low treatment groups found that the groups were still balanced at Age 14 across key demographic and socio-economic variables.

Figure 2: Sample over time

Key Findings

All the results were estimated using permutation tests, with adjustments for attrition using inverse probability weights and for multiple hypotheses testing using the stepdown procedure.

1.    Cognitive development

Cognitive skills: Similar to previous waves, the high treatment group had significantly higher cognitive development compared to the low treatment group at Age 14 – a gap of 0.70 standard deviations which closely mirrors the results at Ages 5 and 9, and substantially outperforms the international literature for similar home visiting interventions. Significant and sustained effects were found for spatial ability, verbal ability, and non-verbal reasoning skills.

Figure 3: Overall cognitive development

Spatial Ability: 17% of high treatment group children scored above the norm in spatial ability, compared to just 4% of the low treatment group.

Working Memory: Children in the high treatment group had significantly better working memory compared to the low treatment group (0.52 of a standard deviation); however, there were no differences on other dimensions of executive functioning including attention flexibility and inhibitory control. 

These results demonstrate the sustained impact of PFL almost 10 years after the families finished the programme.

Table 1: British Ability Scales & NIH Executive Functioning

Note: M_High is the average score of the high treatment group and M_Low is the average score of the low treatment group. A p-value less than 0.100 means that the difference between the high and low treatment groups is statistically significant. The effect size is a measure of how large the difference between the high and low treatment group is in terms of standard deviations.

2.    Socio-Economic development

Socio-Emotional Gains: By Age 14, neither general socioemotional development nor the mental health of the high and low treatment groups significantly differed. Both groups scored similarly on measures such as conduct problems, emotional problems, hyperactivity, peer relationships, and prosocial behaviour.

Mental Health: Over 40% of the PFL cohort (high and low treatment groups) met the cutoff for depressive symptoms, versus just 16% in a nationally representative sample from the Growing Up in Ireland study. Rates of conduct and emotional problems, hyperactivity, and peer issues were much higher in both PFL groups compared to the national average.

Attention Span: There was one persistent benefit of the programme: children in the high treatment group had significantly fewer attention problems (41%) compared to children in the low treatment group (63%).

Figure 4: % Children at risk of attention problems

3.    Health & Nutrition

Obesity Risk: The programme had a significant impact on reducing the risk of obesity. Specifically, 16% of the high treatment group had an ‘at-risk’ waist-to-height ratio compared to 44% in the low treatment group. A high waist-to-height ratio in adolescence is linked to a greater risk of developing health problems later in life.

Nutrition: However, in comparison to national norms, adolescents in the PFL cohort (both high and low treatment groups) demonstrated poorer eating habits in terms of lower rates of daily breakfast, fruit, and vegetable consumption: only 43% of PFL boys and 24% of PFL girls reported eating breakfast daily, compared to 62% and 46%, respectively, in the national sample.

Figure 5: % Children at risk of obesity

4.    Educational Engagement & Expectations

College Aspiration: The high treatment group had significantly higher expectations for their education, with 66% intending to enrol in college or university, compared to just 51% in the low treatment group. Thus, for those who got the more intensive intervention, it demonstrates a significant change in educational goals against a backdrop where only 6% of their parents have a college degree.

Engagement and Time Use: The programme had no impact on current educational practices. There was minimal difference between the groups in terms of school engagement metrics such as absenteeism rates, feeling of belonging, and enjoying school. Additionally, the amount of time spent on homework, social media, and the internet was similar, suggesting that the intervention had no effect on how teenagers allocated their time or participated in school on a daily basis.

Figure 6: % Intention to go to University

5.    Parent-Child Relationships

Bonds:  Adolescents in the high treatment group were significantly more likely than those in the low treatment group to rely on their mothers for emotional support; 75% of them talk to their mothers when they were worried, compared to 42% in the low treatment group.

Parenting style:  The high treatment group also reported that their mothers and fathers were more likely to encourage or help them with something important, with effect sizes of 0.48, and 0.48 standard deviations respectively. In addition, the low treatment group was more likely to report that their mothers tell them it is important to study (79% in the low treatment group vs 63% in the high treatment group). It is possible that the parents of high treatment children do not need to remind their children to study given their higher cognitive skills.

Figure 7: Parent-Child Relationship

Conclusion

The PFL programme is one of the few experimental home visiting interventions with evidence of long-term impacts lasting into adolescence, ten years after the families completed the programme. While comparisons across studies are challenging due to differing goals, target groups, and delivery methods (Gomby et al. 1999), PFL’s larger cognitive effects may stem from its prenatal start, extended duration, multiple components, and inclusive eligibility. Unlike most programmes, PFL begins earlier and lasts longer, which may explain its consistent impacts on cognitive skills, working memory, and attention, but not on social-emotional skills. This suggests lasting changes in brain areas highly responsive to early intervention, such as the frontal lobe (Knudsen et al., 2006). Importantly, the sustained and positive results may also reflect the strong parent–home visitor relationships, which had sufficient time to develop.

In total, one-quarter of the 105 outcomes tested reached conventional levels of statistical significance in the individual tests, and seven of the 20 stepdown tests (35%) were significant. This suggests that the findings were unlikely to be a result of random errors and that the programme continues to have a significant impact on families. While 43% of the original sample participated at Age 14, the treatment groups were still balanced on all key baseline characteristics. Thus, the results are unlikely to be subject to bias. The sizable advantages generated by the PFL programme are likely to have positive impacts on the participant’s outcomes throughout life. Thus, it is critical that we continue to track the PFL cohort as they progress through secondary school and into higher level education.

Policy Recommendations

The results of the PFL study align strongly with Irish Government policy on investing in children, particularly its focus on early intervention and prevention. National frameworks such as First 5: A Whole-of-Government Strategy for Babies, Young Children and their Families 2019–2028 emphasize the importance of supporting children from the earliest stages to reduce inequalities and promote long-term wellbeing. PFL’s evidence of sustained cognitive benefits into adolescence from a prenatal, intensive home-visiting programme reinforces this policy direction, demonstrating that investment in early childhood delivers lasting developmental returns. Moreover, its emphasis on long-term, relationship-based supports for families reflects policy priorities around strengthening parenting, addressing disadvantage, and ensuring more equitable opportunities for children.

The PFL findings have led to its expansion to ten other Irish communities in Bray, Athy, Newbridge, Balbriggan, Finglas, Ballinasloe, Castlebar, Bagenalstown, Kilrush, and Ballaghaderreen. PFL’s research has also received international recognition. The US Department of Health & Human Services officially recognised PFL by including it in the “Home Visiting Evidence of Effectiveness” list based on a review of PFL studies.  It is the only Irish programme eligible for US federal and state funding. In partnership with Nobel Laureate, Professor James Heckman, a second PFL study, called Creciendo Juntos, began in 2023. Working with the local community in Chicago, PFL has been culturally and socially adapted to serve 250 Latino families.  

In sum, PFL demonstrates that providing support to families from the earliest years is an effective long-term strategy. This suggests that the Government should continue to invest in the Area-Based Childhood (ABC) Programmes and the Prevention, Partnership & Family Support Programme. It also supports the Government’s decision to expand home visiting services and develop the National Home Visiting Programme. This approach is also supported by Doyle (2024) in a review of the cost effectiveness of home visiting which found that the average cost-benefit ratio of home visiting programmes is 1.6:1, with the majority of the returns accruing to the General Exchequer due to increased earnings. Thus, investing in parenting programmes early in life is not only an effective means of reducing inequality, but it also generates a positive return for society.

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