From unequal injuries to unequal learning? Socioeconomic gradients in childhood concussions and the impact on children's academic performance.

Previous research identifies stark socioeconomic disparities in child injuries, yet research on the repercussions hereof on other aspects of children's lives remains sparse. This paper tests whether social gradients in minor traumatic brain injuries (mTBIs or concussions) contribute to corresponding inequalities in children's academic performance. Previous research on this topic is mostly based on small samples and confounded by non-random selection into experiencing mTBIs. We improve on prior research by using high quality, large N, administrative registry data. Further, we control for selection into having an mTBI via comparing the test score progression of children having an mTBI with children who experience an mTBI in later years (staggered difference-in-differences). Based on Danish ER/hospital records and national test score data, we find that children from families with lower earnings and less education are more likely to experience an mTBI and that having an mTBI negatively correlates with reading test scores. However, comparing present with future mTBI cases, we show that having an mTBI within a year before a test does not negatively affect children's reading scores. Our findings suggest that negative correlations between mTBIs and academic performance more likely reflect socioeconomic gradients in mTBI incidents rather than a direct causal effect. Further, socioeconomic gradients in mTBI incidents do not significantly contribute to corresponding disparities in academic performance.

Inequality in learning opportunities during Covid-19: Evidence from library takeout.

Research shows that Covid-19 enhanced inequality in families' learning environments. We use register data from Denmark to analyze inequality in families' takeout of digital children's books from public libraries. Our register data, which include more than 55 million observations of families' daily library takeout, show that the socioeconomic gradient in library takeout (by parents' education and income) that existed before the Covid-19 lockdown increased after the lockdown. We also find that the increase in the socioeconomic gradient during Covid-19 was weaker in immigrant than in native families, stronger in families with recent experience in taking out digital materials from the library, and stronger in families with children in the early stages of elementary school. Overall, our results suggest that Covid-19 increased inequality in learning opportunities because better off families were more successful at using libraries during the pandemic than worse off families.

Family Size and Educational Attainment: Cousins, Contexts, and Compensation.

This paper analyses the effect of family size on children's educational attainment using a new research design that combines fixed effects and instrumental variable (IV) approaches. We use (a) data on first cousins who belong to the same extended family but to different nuclear families to control for extended family fixed effects and (b) variation in in-married spouses' number of siblings (a proxy for their fecundity and preferences) as an IV for variation in family size within extended families. We find that family size has a negative causal effect on educational attainment and, moreover, that the negative effect is smaller in families with stronger social ties. Our results suggest that contextual characteristics outside the nuclear family moderate the negative effect of family size on children's educational attainment.