SCS aimed to explore in detail the associations of diet, other risk factors, and disease rates between populations and among individuals within populations. The study involves nearly 13,000 men from 16 cohorts across 7 countries (United States, Finland, Netherlands, Italy, Greece, former Yugoslavia, and Japan), chosen for cultures apparently contrasting in lifestyle, eating habits, risk factor levels, and, presumably, incidence and mortality from CHD. The men were enrolled and examined for the first time from 1958 to 1964 when they were between 40 and 59 years old. Follow-up surveys were conducted after 5 and 10 years for all surviving men, with cardiovascular risk factors also followed up in 9 European cohorts after 25, 30, 35 and 40 years. The collection of mortality data for the 16 cohorts continued up to 25 years for 3 cohorts, 45 years for another 3 cohorts and for 10 cohorts until the 50th anniversary of the Seven Countries Study.