The Roles of Cognitive and Non-Cognitive Skills in Moderating the Effects of Mixed-Ability Schools on Long-Term Health

We examine heterogeneity in the impacts of exposure to mixed-ability 'comprehensive' schools in adolescence on long-term health and smoking behaviour. We explore the roles that cognitive and non-cognitive skills may play in moderating these impacts. We use data from the 1958 National Child Development Study (NCDS) cohort, whose secondary schooling years lay within the transition years of a major reform that transformed secondary education in England and Wales from a selective system of schooling to mixed-ability comprehensive schools. We adopt a local instrumental variables approach to estimate person-centred treatment (PeT) effects of comprehensive over selective schooling system. Our results indicate that the newer comprehensive schooling system produced significant negative effects on long-term health and increased smoking behavior among a small fraction of individuals, for whom the effects were persistent over time. The ATE and TT were quantitatively similar and statistically insignificant indicating that cognitive abilities, the major driver for selection in to comprehensive schools, did not moderate the effects. The PeT effects indicate that individuals with lower non-cognitive skills were most likely to be negatively affected by exposure to mixed-ability schools. Our results also show that cigarette smoking could be a leading transmission channel of the long-term impact on health outcomes