The Lothian Birth Cohort study consists of a cohort of 1 091 individuals born in 1936 (LBC1936). Most subjects lived independently in the Lothian region (Edinburgh city and surrounding area) of Scotland. The majority of subjects took part in the Scottish Mental Surveys of 1947, and were assessed again on cognition and medical traits at roughly 70 years of age.48 A fuller description about participant recruitment and testing can be found elsewhere.48,49 There were 888 subjects (447 female) who successfully filled in the NEO-FFI and survived the DNA and genotyping quality control procedures. The mean age of these 888 subjects was 69.6 (SD=1). The mean ages of the men and women were the same.
