Analyzing national registry data, the authors use within-sibling design and two-sample Mendelian randomization to identify bidirectional causal relationships between educational attainment (EA) and mental health conditions, demonstrating that lower levels of EA were differentially associated with some disorders, such as major depressive disorder, but that attention-deficit/hyperactivity disorder causally affected EA.
- Perline A. Demange
- Dorret I. Boomsma
- Michel G. Nivard