Richard Breen, Seongsoo Choi, Anders Holm Sociological Science, July 8, 2015 DOI 10.15195/v2.a17 Abstract The role of education in the process of socioeconomic attainment is a topic of long standing interest to sociologists and economists.

Attention Deficit/Hyperactivity Disorder (ADHD) is negatively associated with a range of academic achievement measures. We use Danish administrative register data to study the impact of medical treatment of ADHD on children’s academic performance assessed by student grade point average (GPA). Using administrative register data on children, who begin medical treatment, we conduct a natural experiment and exploit plausible exogenous variation in medical nonresponse to estimate the effect of medical treatment on school-leaving GPA. We find significant effects of treatment on both exam and teacher evaluated GPAs: Compared to consistent treatment, part or full discontinuation of treatment has large significant negative effects reducing teacher evaluation and exam GPA with .18 and .22 standard deviations, respectively. The results demonstrate that medical treatment may mitigate the negative social consequences of ADHD. Placebo regressions indicate that a causal interpretation of our findings is plausible.

We propose a model of educational decision-making based on rational choice theory in which students use signals about academic ability to make inference about the costs and benefits of different educational options. Our model is simple, extends ideas from previous models, and has testable implications. We test our model using data on Danish monozygotic twins and find that (i) students who receive a positive signal about their academic ability have a higher likelihood of enrolling in and completing a college-bound track compared with those who do not; (ii) the effect of the signal is stronger for students from low socio-economic status (SES) backgrounds than for those from high-SES ones; and (iii) for low-SES students the effect is stronger on enrolment than on completion. Our results suggest that signals about academic ability affect educational decisions in general; they are more important for students who do not have a family ‘push’ to avoid downward social mobility; and they affect educational inequality by making low-SES students too optimistic about their likelihood of completing the college-bound track.

Earlier studies report inconsistent associations between education and cognitive aging. We assessed the association, accounting for selective dropout due to death or dementia, and, in a subsample, accounting for confounding by early-life intelligence. Data from the Danish component of the Survey of Health, Ageing and Retirement in Europe (n = 3,400) were linked to registry data (education records, dementia diagnoses, and mortality) and the Danish Conscription Database (youth intelligence measurements for 854 men). Word recall and verbal fluency were assessed up to 4 times over 10 years (2004–2013) and combined by averaging the z scores. We fitted a joint model linking a time-to-event model for dementia or death to a linear mixed-effects model for cognitive change. Rate of cognitive decline was slower among people with high education compared with low education (β = 0.112, 95% confidence interval (CI): 0.056, 0.170). Adjusting for youth intelligence did not attenuate the association between education and cognitive decline (crude β = 0.136, 95% CI: 0.028, 0.244 vs. adjusted β = 0.145, 95% CI: 0.022, 0.269). The results suggest that higher education may slow cognitive decline in later life. In this sample, results changed little when accounting for selective attrition and confounding by intelligence.