Commentary: Intelligence in youth and all-cause mortality: some problems in a recent meta-analysis.

Experience Study. Psycho-Oncology 2009;18:1122–26. 80 Taylor MD, Hart CL, Davey Smith G et al. Childhood IQ and social factors on smoking behaviour, lung function and smoking-related outcomes in adulthood: Linking the Scottish Mental Survey 1932 and the Midspan studies. Br J Health Psychol 2005;10:399–410. 81 Bartels M, Rietveld MJH, Van Baal GCM, Boomsma DI. Heritability of educational achievement in 12-year-olds and the overlap with cognitive ability. Twin Res 2002;5: 544–53. 82 Johnson W, McGue M, Iacono WG. Genetic and environmental influences on academic achievement trajectories during adolescence. Dev Psychology 2006;42:514–32.