Individual heterogeneity and reverse causality in the relationship between migraine headache and educational attainment

A recent study by Rees and Sabia (2011) found migraine headache was negatively related to educational attainment even after accounting for the influence of family-level unobservables. The current study explores whether this relationship is attributable to unmeasured individual heterogeneity in the form of personality by using non-migraine headache as a placebo. In addition, it explores the degree to which the negative relationship between migraine headache and educational attainment can be explained by reverse causality using mother's migraine status as an instrument. We conclude that the estimates reported by Rees and Sabia (2011) likely reflect the causal effect of migraine headache on educational attainment.