The Effect of Adolescent Health on Educational Outcomes: Causal Evidence using ‘Genetic Lotteries’ between Siblings

There has been growing interest in using specific genetic markers as instrumental variables in attempts to assess causal relationships between health status and socioeconomic outcomes, including human capital accumulation. In this paper we use a combination of family fixed effects and genetic marker instruments to show strong evidence that inattentive symptoms of ADHD in childhood and depressive symptoms as an adolescent are linked with years of completed schooling. Our estimates suggest that controlling for family fixed effects is important but these strategies cannot fully account for the endogeneity of poor mental heath. Finally, our results demonstrate that the presence of comorbid conditions present immense challenges for empirical studies that aim to estimate the impact of specific health conditions.