Educational Policy and the reporting of ADHD symptoms

Attention Deficit Hyperactivity Disorder (ADHD) is the most commonly diagnosed mental disorder among American children. ADHD hinders a child's cognitive development and has a lasting impact on human capital accumulation and on long run educational and labor market outcomes. Like many forms of mental illness, diagnosis of ADHD is subjective. The subjectivity of the diagnosis not only creates ambiguities in whether ADHD is over- or under- diagnosed but it also opens the door to moral hazard. Parental reporting of symptoms of ADHD can be related to the child actually having the condition or many other medical and social conditions that the child may be experiencing. In this paper we examine how incentives built into school policy, where teachers are held accountable for their student’s achievement, can affect the underlying distribution of the reporting of symptoms of ADHD by parents. School accountability laws provide the incentive for teachers to manipulate the testing pool by removing marginal students from the counted population by having them diagnosed as disabled. To study this question we use data form the National Longitudinal Survey of Youth and examine how the distribution of the count of mother reported ADHD changes across time and across regions of the US. We employ Stochastic Dominance methods to show that changes in educational policy not only had influence the average American child, but had uniform consequences across an entire distribution of children. We also examine whether the effect of educational policy changes on the ADHD distribution is concentrated among particular sub-groups parsed by race, household structure, income status, and maternal education level. Our findings are shown to be robust against a variety of different tests of stochastic ordering.