Neonatal health of parents and cognitive development of children.

It is well-established that neonatal health is a strong predictor of socioeconomic outcomes later in life, but does neonatal health also predict key outcomes of the next generation? This paper documents a surprisingly strong relationship between birth weight of parents and school test scores of their children. The association between maternal birth weight and child test scores corresponds to 50-80 percent of the association between the child's own birth weight and test scores across various empirical specifications, for example including grandmother fixed effects that isolate within-family differences between mothers. Paternal and maternal birth weights are equally important in predicting child test scores. Our intergenerational results suggest that inequality in neonatal health is important for inequality in key outcomes of the next generation.

The Strengths and Difficulties Questionnaire and standardized academic tests: Reliability across respondent type and age.

Exploiting nation-wide data from the Danish National Birth Cohort, we show that children's emotional and behavioral problems measured by the Strengths and Difficulties Questionnaire (SDQ) are closely related to their performance in standardized academic tests for reading and mathematics in sixth grade. The relationship is remarkably linear across the entire distribution for both the total difficulties score and subscale scores of the SDQ; higher scores on the SDQ (more problems) are related to worse performance in academic tests. We assess the similarity across respondent type; parent (child age 7 and 11), teacher (child age 11) and self-reported scores (child age 11), and find that teacher and parent reported scores have very similar slopes in the SDQ-test score relationship, while the child reported SDQ in relation to the academic test performance has a flatter slope.

The gift of time? School starting age and mental health.

Using linked Danish survey and register data, we estimate the causal effect of age at kindergarten entry on mental health. Danish children are supposed to enter kindergarten in the calendar year in which they turn 6 years. In a "fuzzy" regression-discontinuity design based on this rule and exact dates of birth, we find that a 1-year delay in kindergarten entry dramatically reduces inattention/hyperactivity at age 7 (effect size = -0.73), a measure of self-regulation with strong negative links to student achievement. The effect is primarily identified for girls but persists at age 11.

Discharge on the day of birth, parental response and health and schooling outcomes.

Exploiting the Danish roll-out of same-day discharge policies after uncomplicated births, we find that treated newborns have a higher probability of hospital readmission in the first month after birth. While these short-run effects may indicate substitution of hospital stays with readmissions, we also find that-in the longer run-a same-day discharge decreases children's 9th grade GPA. This effect is driven by children and mothers, who prior to the policy change would have been least likely to experience a same-day discharge. Using administrative and survey data to assess potential mechanisms, we show that a same-day discharge impacts those parents' health investments and their children's medium-run health. Our findings point to important negative effects of policies that expand same-day discharge policies to broad populations of mothers and children.

Cognitive fatigue influences students' performance on standardized tests.

Using test data for all children attending Danish public schools between school years 2009/10 and 2012/13, we examine how the time of the test affects performance. Test time is determined by the weekly class schedule and computer availability at the school. We find that, for every hour later in the day, test performance decreases by 0.9% of an SD (95% CI, 0.7-1.0%). However, a 20- to 30-minute break improves average test performance by 1.7% of an SD (95% CI, 1.2-2.2%). These findings have two important policy implications: First, cognitive fatigue should be taken into consideration when deciding on the length of the school day and the frequency and duration of breaks throughout the day. Second, school accountability systems should control for the influence of external factors on test scores.

Care around birth, infant and mother health and maternal health investments - Evidence from a nurse strike.

Care around birth may impact child and mother health and parental health investments. We exploit the 2008 national strike among Danish nurses to identify the effects of care around birth on infant and mother health (proxied by health care usage) and maternal investments in the health of their newborns. We use administrative data from the population register on 39,810 Danish births in the years 2007-2010 and complementary survey and municipal administrative data on 8288 births in the years 2007-2009 in a differences-in-differences framework. We show that the strike reduced the number of mothers' prenatal midwife consultations, their length of hospital stay at birth, and the number of home visits by trained nurses after hospital discharge. We find that this reduction in care around birth increased the number of child and mother general practitioner (GP) contacts in the first month. As we do not find strong effects of strike exposure on infant and mother GP contacts in the longer run, this result suggests that parents substitute one type of care for another. While we lack power to identify the effects of care around birth on hospital readmissions and diagnoses, our results for maternal health investments indicate that strike-exposed mothers-especially those who lacked postnatal early home visits-are less likely to exclusively breastfeed their child at four months. Thus reduced care around birth may have persistent effects on treated children through its impact on parental investments.