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Nordic Economic Policy Review 2026

Comments on Stine Nyhus Larsen et al.: Childhood and Adolescent Interventions in a Danish Setting


Marjo Kyllönen and Kristiina Hannukainen
The Larsen et al. article aimed to estimate pooled effects on children’s learning and to explain between-study variation using cost-standardised effect sizes and coded information on intervention content, delivery, and context collected during a principal investigator survey. The findings indicate that education interventions in Denmark have, on average, led to minor improvements, with meaningful variations in the effects and cost-effectiveness due to the design and context.
The effects of educational interventions, particularly in the context of the Nordic welfare state – specifically in Finland – are of significant interest to us. As noted in the article, the focus on interventions also serves as a research tool to highlight the inequalities in income and wealth that affect learning and wellbeing.
It was a pleasure to receive an article for evaluation that is timely and addresses a topic that has not been sufficiently scrutinised from the perspective of education providers. This evaluation also affords us, as educational organisers, the opportunity to articulate our insights regarding the significance of collaboration between academia and practice in shaping urban policy.

1 The City of Helsinki relies on research data to develop its operations

The article by Larsen et al. was interesting and inspiring. We found many similarities with the areas we are also eager to explore and understand better in Helsinki. The City of Helsinki is the largest education provider in Finland, serving approximately 200,000 individuals, from early childhood to adult education. We have over 15,000 professionals working at more than 700 locations. Our goal is to foster positive learning and wellbeing for all citizens in Helsinki while working collaboratively to build a sustainable future.
We need to work towards equitable learning, strengthen core knowledge and skills, and support the development of social and emotional competencies. In our Education 2030 strategy (City of Helsinki, 2024), we emphasise the importance of research and data. We recognise that to succeed in our mission, our efforts must be guided by research and evidence. As such, we leverage research data to promote growth and development in our learners.
We encourage our schools and educators not only to adopt a variety of teaching methods but also to use our research data to assess and enhance pedagogical resources. As highlighted in the article, high-quality interactions between teachers and students, well-targeted curricula, enriched learning environments, and support for teachers’ professional development are linked to positive educational outcomes.

2 Why is collaboration between academia and decision makers essential? 

The Mayor of Helsinki recently unveiled a new city strategy for 2025-2029 (City of Helsinki, 2025), stating, “We rely on research data in the development of our operations.” While we undertake our own research, we firmly believe that collaboration with local universities is vital for enhancing and developing our initiatives. Helsinki aspires to be a pioneering force in impact research and its application for the betterment of children and young people.
We recognise that education constitutes a significant investment in the future, with half of the city budget dedicated to educational services. We must ensure our resources are allocated and utilised effectively. For example, we are channelling needs-based funding into early childhood education and care (ECEC) and schools in less affluent socio-economic districts. In Helsinki, our goal is to alleviate the adverse effects of regional segregation on educational institutions and learners through targeted funding in the education sector. A critical question arises: how can we ascertain that utilising these resources effectively reduces disparities?
The phenomena of polarisation and segregation are escalating challenges in Helsinki. While our educational ethos emphasises principles of equality and equity, the latest PISA research (2022) indicates that basic education is falling short in bridging the gaps.
As educational providers, our challenge is to determine whether our structures and pedagogical practices have a positive impact on children’s growth and learning outcomes. Randomised controlled trials (RCTs) are integral to our broader evaluation framework. These experiments furnish education providers and policymakers with valuable insights on enhancing educational practices and improving learning outcomes.
The findings presented by Larsen and colleagues have significant implications for Helsinki: interventions aimed at teachers in schools and educators in daycare and preschool settings are markedly more effective than those directed at children or their parents. Fully manualised interventions tend also to be less effective than non-manualised or partially manualised ones. Results show that language outcomes typically exhibit substantially lower effect sizes than those in mathematics, whereas other outcomes, often related to vocabulary acquisition, demonstrate larger effects. Interventions designed for children under school age (preschoolers) are more effective than those targeting older children. Notably, while interventions that prioritise quality enhancement generally yield lower effects than those focused on increasing quantity, those emphasising structural quality tend to be more effective than those centred on process quality or learning formats.
Interestingly, the evaluation design (RCT versus other methodologies) does not significantly influence effect sizes. This indicates that, on average, non-experimental evaluation designs do not substantially overestimate or underestimate true effect sizes (as determined by RCTs) in our sample. However, this does not imply the absence of bias in individual studies, as different forms of bias may take various forms and potentially offset each other on average.
Language assessments yield significantly poorer outcomes compared to mathematics and other measures. Interventions aimed at preschool children are more cost-effective than those focused on older children and young adults, especially when delivered in daycare settings. Additionally, interventions targeting educators are more cost-effective, whereas fully manualised interventions tend to be less so. 
To achieve the objectives stipulated in our City Strategy—that every local school in Helsinki is a high-quality educational institution—we require a more extensive, research-informed understanding of the effectiveness of routine practices in schools and early childhood education.
To ensure that every child and young person acquires the necessary skills and competencies to succeed in further education and professional life, we must deepen our understanding of how best to support our schools and teachers in choosing the most effective pedagogical approaches. It is important to note that in Finland, teachers have considerable pedagogical autonomy in selecting classroom tools and methods, a freedom we respect and value.
We are particularly eager to deepen our understanding of how to improve the learning experiences and developmental outcomes of disadvantaged children and young people. 

3 Conclusions

This article and its meta-analysis present intriguing findings that resonate with our current focus in research collaboration with academia. Here are some reflections based on the article that warrant consideration:
  • Carefully designed interventions have a positive impact on children's learning outcomes at all ages.
  • Interventions aimed at younger children are particularly effective and promising.
One critical observation from the meta-analysis is that interventions targeting educators have been more effective than those directed at children and their parents.
  • Given that a pupil’s background is the strongest predictor of learning outcomes, how can we identify effective methods to support and guide families?
 In conclusion, this aligns with our vision outlined in the new City Strategy: a Helsinki of which we can be proud (City of Helsinki, 2025). Realising our vision will require research partnerships with scholars and universities, and the insights in the article by Larsen and colleagues are particularly relevant to our new strategy. We need research collaboration with universities, as well as long-term, well-designed interventions that also target preschool and early childhood education.  

References

City of Helsinki. (2024). Helsinki learns – Future competences: Education 2030. Retrieved from: https://www.hel.fi/static/kasko/helsinkioppii/helsinki-learns-future-competences.pdf
City of Helsinki. (2025). Helsinki city strategy 2025–2029. Retrieved from: https://www.hel.fi/en/decision-making/strategy-and-economy/strategy