What are the comparative effect sizes of early childhood educational interventions across different age groups and learning domains?

Early childhood educational interventions demonstrate varying effectiveness across domains, producing effect sizes of 0.10-1.45 standard deviations for cognitive outcomes, 0.18-1.22 for mathematics, 0.10-0.44 for language (up to 1.10 for literacy), and 0.19-0.56 for socioemotional and motor development, with comparable benefits observed across preschool and infant age groups.

Abstract

Early childhood educational interventions yield effect sizes that vary by learning domain, intervention modality, and age group. Studies targeting cognitive outcomes report gains ranging from 0.10 to 1.45 standard deviations—with intensive, multi-year programs (e.g., Ramey and Ramey, 2023) achieving the largest benefits—while language-focused programs generally produce improvements of 0.10 to 0.44 standard deviations, with some literacy interventions reaching 1.10. Mathematics interventions typically exhibit effects from 0.18 to 1.22 standard deviations, especially when curriculum-based and structured (as in Yıldız et al., 2025 and Clements et al., 2011). Socioemotional and motor development interventions tend to yield modest gains (approximately 0.19–0.56), a range further supported by evaluations of responsive caregiving and physical activity programs. Most studies concentrate on preschool-aged children, though interventions for infants show comparable benefits. Greater intervention intensity, duration, and multi-component design are associated with larger effects, according to the reported findings.

Methods

We analyzed 40 sources from an initial pool of 997, using 8 screening criteria. Each paper was reviewed for 6 key aspects that mattered most to the research question.

Papers identified with Elicit search

• n = 997

Papers screened using:

• Population Age Range: Does the study focus on children aged 0-8 years (early childhood period)?
• Quantitative Data Availability: Does the study report quantitative effect sizes or provide sufficient quantitative data to calculate effect sizes?
• Study Design Rigor: Is the study a randomized controlled trial, quasi-experimental study, or controlled study with comparison groups?
• Educational Setting: Is the intervention implemented in early childhood educational settings (e.g., preschools, kindergartens, childcare centers, or home-based educational programs)?
• Learning Domain Focus: Does the intervention target specific learning domains (cognitive, language, literacy, numeracy, social-emotional, or motor skill development)?
• Typical Development Population: Does the study include typically developing children (rather than focusing solely on children with diagnosed developmental disabilities or special needs)?
• Intervention Component: Does the study include an intervention component (rather than being purely observational)?
• Educational vs. Medical Focus: Is the intervention primarily educational in nature (rather than primarily focused on medical or therapeutic treatments)?

We considered all screening questions together and made a holistic judgement about whether to screen in each paper.

Data extraction

We asked a large language model to extract each data column below from each paper:

• Study Design Type: Identify the specific type of study design used.

• Intervention Type and Components: Comprehensively list all components of the educational intervention.

• Participant Demographics: Extract participant details:

  • Age range of children
  • Socioeconomic status (if reported)
  • Risk factors or special circumstances
  • Total sample size
  • Gender distribution (if reported)

• Outcome Domains and Measurement: List all primary outcome domains measured.

• Long-term Outcomes: Identify and extract any long-term outcomes measured beyond immediate child development.

• Geographical and Contextual Factors: Extract geographical context and any environmental factors.

Results

Characteristics of Included Studies

Effects

Effect Sizes by Age Group

Effect Sizes by Learning Domain

Cognitive Development:

• Effect sizes reported in the included studies range from 0.10–1.45 standard deviations, with larger effects observed in intensive, multi-year interventions.

Language Development:

• Effect sizes typically ranged from 0.10–0.44 standard deviations, with some studies reporting larger effects for emergent literacy.

Mathematics:

• Effect sizes ranged from 0.18–1.22 standard deviations, with the largest effects in structured, curriculum-based interventions.

Socioemotional Development:

• Effect sizes were generally small to moderate.

Motor Development:

• Physical activity and fine motor interventions yielded moderate effects.

Academic Achievement:

• Reading and math achievement effect sizes ranged from 0.10–0.60 standard deviations.”

Generalizability and Study Context

• The included studies spanned high-, middle-, and low-income countries, with interventions adapted to local contexts.
• Most studies focused on low-income or high-risk populations, which may limit generalizability to more advantaged groups.
• Interventions were delivered in a variety of settings, including center-based, home-based, community, and digital environments. The context of delivery influenced both feasibility and effectiveness.