COHORT PROFILE Cohort Profile: The Doetinchem Cohort Study

The origin of the Doetinchem Cohort Study lies within the Monitoring Project on Cardiovascular Disease Risk Factors (MP-CVDRF), which was aimed at providing prevalence estimates of cardiovascular disease risk factors, such as smoking, blood pressure and serum cholesterol levels. During 1987–91 each year an ageand sex-stratified random sample of men and women aged 20–59 years, was invited to participate. The MP-CVDRF was carried out in three towns in The Netherlands (Amsterdam in the west, Doetinchem in the east and Maastricht in the south), and from each of the three towns, about 12 000 men and women were examined. In the subsequent Monitoring Project on Chronic Disease Risk Factors (MORGEN-project), carried out from 1993–97, in Doetinchem only respondents from the MP-CVDRF were invited to participate, while in Amsterdam and Maastricht again random samples from the general population were examined. The protocol was extended, because the focus broadened from cardiovascular to other chronic diseases such as cancer, diabetes, musculoskeletal disorders and COPD. Due to extension of the protocol, with similar budget, not all 12 405 participants in the MP-CVDRF could be re-invited. Instead, a random sample of in total 7769 of the respondents at baseline was invited for re-examination. This random sample is considered the basis of the cohort (Figure 1).