Understanding cross-national similarities and differences in foundational numeracy skills: meta-analytical evidence from the Numeracy Screener

Children’s early numerical abilities are a strong correlate of their later numerical and mathematical skills. The Numeracy Screener is an evidence-based, free paper-and-pencil assessment aimed at measuring children’s ability to compare both symbolic (e.g., single-digit Hindu-Arabic numerals) and non-symbolic (e.g., dot arrays) magnitudes. In this preregistered study, we report Numeracy Screener data collected from 9,118 students aged 3 to 13 years across 20 countries. Multi-level meta-analyses were conducted to investigate the relations between symbolic and non-symbolic numerical magnitude comparison skills, performance differences between these skills, and the relation between comparison skills and mathematical abilities. We also examined the moderating effects of country-level socioeconomic and cultural factors, as well as age, on the effect sizes of the associations and differences. Results showed a strong positive correlation between symbolic and non-symbolic comparison skills. No overall performance difference was observed between the two types of magnitude comparison skills. However, younger participants performed better on non-symbolic than symbolic tasks, whereas older students performed better on symbolic relative to non-symbolic comparisons. Both symbolic and non-symbolic numerical magnitude skills were positively correlated with mathematical performance, with a significantly stronger association for symbolic comparison skills. Furthermore, country-level factors such as the Human Development Index and educational investment moderated the association between non-symbolic comparison skills and mathematical abilities. These findings highlight the role of basic numerical skills in mathematical performance and suggest that socioeconomic and educational factors influence this relation. Future research should consider country-specific and contextual factors to better understand how foundational numerical skills are developed.