Articles & working papers

Peer-reviewed journal articles

Solaz A., Panico L., Sheridan A., Schneider T., Dräger J., Waldfogel J., Jiyoon Kwon S., Washbrook E., Perinetti Casoni V. (2024), "Does Family Structure Account for Child Achievement Gaps by Parental Education? Findings for England, France, Germany and the United States", Population and Development Review.

This paper explores the role of family trajectories during childhood in explaining inequalities by maternal education in children’s math and reading skills using harmonized, longitudinal, and nationally representative surveys, which follow children over the course of primary and lower secondary school in four high-income countries (England, France, Germany, and the United States). As single parenthood and family transitions are more likely among less educated parents and are associated with fewer resources for children, we explore whether growing up outside a stable two-parent family mediates educational inequalities in math and reading scores.
Results show a strong educational gradient in family trajectories in the four countries, but this varies by child age and by country. Children who experience a family transition record lower test scores, although the magnitude differs by the type of postseparation arrangements.
Overall, family trajectories are strongly associated with children’s math and reading scores but, because of the importance of selectivity in family trajectories, they play only a modest role in explaining the skills gaps by maternal education, considerably less than determinants such as income. The penalties associated with not living within a stable two-parent family are always larger in the United States and England than in France and Germany.


Dräger, J., Schneider, T., Olczyk, M., Solaz, A., Sheridan, A., Washbrook, E., Perinetti Casoni, V, Kwon S. J., & Waldfogel, J. (2023). The relevance of tracking and social school composition for growing achievement gaps by parental education in lower secondary school. A longitudinal analysis in France, Germany, the United States, and England. European Sociological Review.

There is substantial variation in the degree of social stratification in students’ achievement across countries. However, most research is based on cross-sectional data. In this study, we evaluate the importance of social origin, namely, parents’ education, for achievement inequalities during lower secondary school using recent longitudinal microdata form the French Direction de l’Evaluation de la Prospective et de la Performance panel, the German National Educational Panel Study, the US-American Early Childhood Longitudinal Study 1998, and the British Millennium Cohort Study. We evaluate whether country differences can be attributed to different tracking systems or the social composition of schools. We find substantial SES gaps in math achievement progress in all four countries but more pronounced gaps in England and Germany. Yet, within-school SES gaps are similar across countries suggesting that the allocation of students to schools drives country differences. Moreover, we find that between-school tracking in Germany accounts for a large share of the SES gaps, whereas course-by-course tracking seems less important in the other countries. The role of schools’ social composition is similar across countries.

Waldfogel, J., Kwon, S., Wang, Y., Washbrook, E., Perinetti Casoni, V., Olczyk, M., Schneider, T., Panico, L., Solaz, A., Weinert, S., Volodina, A., de la Rie, S., Keizer, R., Nozaki, K., Yamashita, J., Kameyama, Y., & Akabayashi, H. (2023). Inequalities in resources for preschool-age children by parental education: evidence from six advanced industrialized countries. European Journal of Population.

This paper provides new evidence on inequalities in resources for children age 3–4 by parental education using harmonized data from six advanced industrialized countries—United States, United Kingdom, France, Germany, Netherlands, and Japan—that represent different social welfare regime types. We analyze inequalities in two types of resources for young children—family income, and center-based child care—applying two alternative measures of parental education—highest parental education, and maternal education. We hypothesize that inequalities in resources by parental education will be less pronounced in countries where social policies are designed to be more equalizing. The results provide partial support for this hypothesis: the influence of parental education on resources for children does vary by the social policy context, although not in all cases. We also find that the measurement of parental education matters: income disparities are smaller under a maternal-only definition whereas child care disparities are larger. Moreover, the degree of divergence between the two sets of estimates differs across countries. We provide some of the first systematic evidence about how resources for young children vary depending on parents’ education and the extent to which such inequalities are buffered by social policies. We find that while early inequalities are a fact of life in all six countries, the extent of those inequalities varies considerably. Moreover, the results suggest that social policy plays a role in moderating the influence of parental education on resources for children.

Olczyk, M., Gentrup, S., Schneider, T., Volodina, A., Perinetti Casoni, V., Washbrook, E., Kwon, S. J., Waldfogel, J. (2023): Teacher judgements and gender achievement gaps in primary education in England, Germany, and the US, Social Science Research, 116: 102938

We examined whether inaccurate teacher judgements of primary school student achievement correlate with students’ gender and whether such bias contributes to gender achievement gaps in language and mathematics. Our study used ex-post harmonised longitudinal data from England, Germany, and the US. We observed domain-specific teacher judgement bias with a positive bias for girls in the language domain and for boys in mathematics. Furthermore, biased teacher judgements partly mediated the effect of gender on later achievement. Despite these common findings, cross-country differences emerged in the extent of teacher judgement bias as well as its mediation of gender achievement gaps. We conclude that this is a topic of relevance across national contexts and where the institutional and societal setting needs more attention in future research.

Volodina, A., Weinert, S., Washbrook, E., Waldfogel, J., Keizer, R., Perinetti Casoni, V., de la Rie, S., & Kwon, S. J. (2023). Parental education-related gaps in externalising behaviour at age 3-4 years: Evidence from a harmonised framework from the United Kingdom, the United States, and the Netherlands. Child Youth Care Forum.

Background: Research on factors underlying socioeconomic status (SES)-related inequalities in child development mainly focuses on single countries and specific influential factors. Only few studies scrutinize to what extent differences in children’s early behavioural outcomes vary across countries and whether the processes that account for them are common or context-specific.
Objective: The aim of this study was to explore SES-related inequalities and explanatory factors in 3- to 4-year-old children’s externalising behaviour as well as their generalisability across outcome variables (hyperactivity, conduct problems) and countries.
Methods: The study uses harmonised data from three longitudinal large-scale studies conducted in the United Kingdom (UK), the United States (US), and the Netherlands and a decomposition method to comparatively analyse early SES-related gaps and explanatory factors.
Results: Results show that the extent of parental education-related gaps varied across countries. The included explanatory factors accounted for significant amounts of gaps in hyperactivity and conduct problems. Yet, while family income and maternal depressive feelings significantly explained gaps in each facet of externalising behaviour across all three countries, other factors were country-specific. In the US and the UK, health-related factors were additionally relevant for explaining early gaps in both child outcomes; in the UK, also structural aspects of the family significantly explained gaps in conduct problems; no other factors contributed to the explanation of gaps in the Netherlands.
Conclusions: Mechanisms that might reduce SES-related inequalities in child behaviour and that may be helpful when constructing appropriate interventions are partially similar, yet also significantly different between countries and child outcomes.

Panico, L., Boinet, C., Akabayashi, H., de la Rie, S., Kwon, S. J., Kameyama, Y., Keizer, R., Nozaki, K., Perinetti Casoni, V., Volodina, A., Waldfogel, J., Weinert, S., & Washbrook, E. (2023). International differences in gradients in early childhood overweight and obesity: the role of maternal employment and formal childcare attendance. European Journal of Public Health,  33(3): 468–475,

Background: There are significant cross-country differences in socio-economic gradients in later childhood and adulthood overweight/obesity; few studies assess whether this cross-national variation is evident from early childhood. Furthermore, the role of childcare in explaining overweight/obesity gradients might vary across countries, given differences in access, quality and heterogeneity within. Additionally, childcare is linked to parental characteristics such as maternal employment. The interplay between childcare and employment in producing early overweight/obesity gradients has received little attention, and might vary cross-nationally.
Methods: Using harmonized data from six high-quality, large datasets, we explore the variation in gradients in early overweight/obesity (at age 3–4 years old) by parental education across several high-income countries (USA, UK, France, the Netherlands, Germany and Japan). We then assess whether differential formal group care use attenuates some of these gradients, and whether this varies across maternal employment.
Results: Gradients in early childhood overweight/obesity by parental education are evident across several developed countries. Countries with higher overall prevalence of early overweight/obesity did not have the largest inequalities across education groups. The contribution of formal group care to producing these gradients varied across countries and across maternal employment status.
Conclusion: Early childhood inequalities in overweight/obesity are pervasive across developed countries, as noted for older children and adults. However, mechanisms producing these gradients vary across national contexts. Our study shows that, given the right context, quality childcare and maternal employment can successfully support healthy weight trajectories and not contribute (or even reduce) social inequalities in early overweight/obesity.

de la Rie, S., Washbrook, E., Perinetti Casoni, V., Waldfogel, J., Kwon, S. J., Dräger, J., Schneider, T., Olczyk, M., Boinet, C., & Keizer, R. (2023). The role of energy balance related behaviors in socioeconomic inequalities in childhood body mass index: A comparative analysis of Germany, the Netherlands, the United Kingdom, and the United States. Social Science & Medicine, 317, 115575.

Socioeconomic inequalities in childhood Body Mass Index (BMI) are becoming increasingly more pronounced across the world. Although countries differ in the direction and strength of these inequalities, cross-national comparative research on this topic is rare. This paper draws on harmonized longitudinal cohort data from four wealthy countries—Germany, the Netherlands, the United Kingdom (UK), and the United States (US)—to 1) map cross-country differences in the magnitude of socioeconomic inequalities in childhood BMI, and 2) to examine cross-country differences in the role of three energy-balance-related behaviors—physical activity, screen time, and breakfast consumption—in explaining these inequalities. Children were aged 5–7 at our first timepoint and were followed up at age 8–11. We used data from the German National Educational Panel Study, the Dutch Generation R study, the UK Millennium Cohort Study and the US Early Childhood Longitudinal-Kindergarten Study. All countries revealed significant inequalities in childhood BMI. The US stood out in having the largest inequalities. Overall, inequalities between children with low versus medium educated parents were smaller than those between children with high versus medium educated parents. The role of energy-balance-related behaviors in explaining inequalities in BMI was surprisingly consistent. Across countries, physical activity did not, while screen time and breakfast consumption did play a role. The only exception was that breakfast consumption did not play a role in the US. Cross-country differences emerged in the relative contribution of each behavior in explaining inequalities in BMI: Breakfast consumption was most important in the UK, screen time explained most in Germany and the US, and breakfast consumption and screen time were equally important in the Netherlands. Our findings suggest that what constitutes the most effective policy intervention differs across countries and that these should target both children from medium as well as low educated families.

Volodina, A., Weinert, S., Washbrook, E., Waldfogel, J., Kwon, S. J., Wang, Y., & Perinetti Casoni, V. (2022). Explaining gaps by parental education in children’s early language and social outcomes at age 3–4 years: evidence from harmonised data from three countries. Current Psychology, 1-20.

*Awarded the NEPS Publication Prize at the annual NEPS conference for outstanding publications using NEPS data

Child outcomes vary by family’s socioeconomic status (SES). Research on explanatory factors underlying early SES-related disparities has mainly focused on specific child outcomes (e.g., language skills) and selected influencing factors in single countries often with a focus on individual differences but not explicitly on early SES-related gaps. This study uses harmonised data from longitudinal large-scale studies conducted in the United Kingdom, United States, and Germany to examine parental education-related gaps in early child language and social skills. Twelve theoretically proposed family-, child-, and childcare-related factors were systematically evaluated as explanatory factors. In all countries, parental education-related gaps were particularly pronounced for early child language compared to social skills. In the decomposition analyses, the home learning environment was the only measure that significantly explained gaps in all child outcomes across all countries. Early centre-based care attendance, family income, and maternal age at childbirth contributed to gaps in child outcomes with the specific pattern of results varying across outcomes and countries. Maternal depressive feelings significantly contributed only to explaining gaps in children’s social skills. Thus, while some mechanisms found to underpin early parental education-related gaps can be generalized from single-country, single-domain studies, others are outcome- and context-specific.

Olczyk, M., Kwon, S. J., Lorenz, G., Perinetti Casoni, V., Schneider, T., Volodina, A., Waldfogel, J. & Washbrook, E. (2022). Teacher judgements, student social background, and student progress in primary school: a cross-country perspective. Zeitschrift für Erziehungswissenschaft (Journal of Educational Research), 1-26.

This study takes a cross-country perspective to examine whether inaccurate teacher judgements of students’ math skills correlate with student social origin and whether such bias is associated with math achievement in primary school. We focus on England, Germany, and the US because these countries differ in the teachers’ growth mindsets, accountability, the use of standardised tests, and the extent of ability grouping. The data stem from three large-scale surveys, the Millennium Cohort Study for England, the National Educational Panel Study for Germany, and the Early Childhood Longitudinal Study, Kindergarten Class of 2010–11 for the US. At the beginning of primary education, teacher judgements were not entirely consistent with student scores in standardised tests. In England and Germany, teachers underrated students with low-educated parents and overrated those with high-educated parents. In the US, no such differences were found. In all three countries, overrated (or underrated) students performed better (worse) later on. In England and, to a lesser extent, in Germany, we found evidence that biased teacher judgements contribute—over the course of primary school—to widening inequalities in value-added achievement by parental education. Such effects were negligible in the US. Our findings suggest that a cross-country perspective is essential to better understand contextual factors’ role in systematic bias in teacher judgements and its relevance for educational achievement. This study can be seen as a starting point for future research to investigate the mechanisms of such contextual effects more thoroughly.

Pre-prints and working papers or under review

Dräger, J., Washbrook, E., Schneider, T., Akabayashi, H., Keizer, R., Solaz, A., Waldfogel, J., de la Rie, S., Kameyama, Y., Kwon, S. J., Nozaki, K., Perinetti Casoni, V., Sano, S., Sheridan A., & Shikishima, C. (2023). Cross-national differences in socioeconomic achievement inequality in early primary school: The role of parental education and income in six countries. Available as discussion paper on SocArXiv, 18 January 2023.

This paper presents comparative information on the socioeconomic status (SES) gradients in literacy skills at age 6-8, drawing on harmonized national datasets from France, Germany, Japan, the Netherlands, the United Kingdom, and the United States. We investigate whether understanding of comparative SES gradients in early-to-mid childhood depends on the operationalization of SES (parental education, income, or both); and whether differences in inequalities at the end of lower secondary schooling documented in international large-scale assessments are already present when children have experienced at most two years of formal compulsory schooling. We find marked differences in the SES gradient in early achievement across countries that are largely insensitive to the way SES is measured, and that seem to mirror inequalities reported for older students. We conclude that country context shapes the link between parental SES and children’s educational achievement, with country differences rooted in the early childhood period.  


Olczyk, M., Schneider, T., Washbrook, E. & the DICE-team (2021). National context and socioeconomic inequalities in educational achievement - An overview of six high-income countries: France, Germany, Japan, the Netherlands, United Kingdom, and United States. Paris, Ined, Document de travail, 267.

Empirical research repeatedly shows cross-country differences in the extent and distribution of socioeconomic inequalities in educational achievement. This observation is the starting point for the comparative DICE-project (Development of Inequalities in Child Educational  achievement: A Six-Country Study). It aims to improve the understanding of child development by socioeconomic status, operationalised in terms of parental education in six countries: France, Germany, Japan, the Netherlands, the United Kingdom, and the United States. The project  moves beyond cross-sectional and single country snapshots and examines the development of inequalities from 3 years of age up to the end of lower secondary schooling. In this contribution, we introduce the six countries. First, by synthesizing data from a range of international databases we provide a rich and multidimensional characterisation of macrostructural conditions in each country. Linking the contextual situation in the DICE-countries to general theoretical assumptions about the effects of macrostructural conditions, we highlight the implications for cross-national differences in inequalities in educational achievement. Second, we analyse PISA data providing information about achievement test scores at age 15. We study how the different packages of macrostructural characteristics described in the contextual section are reflected in terms of educational inequalities by the end of lower secondary schooling in each country.


In preparation

de la Rie, S. & the DICE Study Team (2022). Parental Leave Policy and Disparities in Infant and Maternal Health: Evidence from Six Advanced Industrialized Countries

We investigate how disparities in infant and maternal health by maternal education vary across six countries that differ strongly in the generosity and universality of their parental leave policies. We document inequalities in birth weight, breastfeeding and maternal depression in the first year of life. In addition, we explore whether and to what extent cross-country variation in health disparities can be attributed to differences in income and maternal employment in the first year of life. We use harmonized data from six advanced industrialized countries – France, Germany, Japan, Netherlands, United Kingdom, and United States -- to answer our research questions.