Table 1.

Overview of measurement rounds of the Doetinchem Cohort Study^a

Name	Monitoring Project on Cardiovascular Disease Risk Factors (MP-CVDRF)	Monitoring Project on Chronic Disease Risk Factors (MORGEN-Project)	Doetinchem cohort study, round 3	Doetinchem cohort study, round 4	Doetinchem cohort study, round 5	Doetinchem cohort study, round 6
Years	1987–91	1993–97	1998–2002	2003–07	2008–12	2013–17
Age range	20–59 yrs	26–65 years	31–70 years	36–75 years	41–80 years	46–86 years
Numbers participated	12404b	6117	4918	4520	4018	About 3450
Response	62%	79%	75%	78%	78%	About 77%
Numbers invited	20154	7768b	6581	5783	5136	About 4474
Who were invited	Age- and sex-stratified random sample of population	A random two-thirds of those measured in round one	Those who were invited in round 2 excluding those who emigrated, actively withdrew from the study or died	Those who were invited in round 3 excluding those who emigrated, actively withdrew from the study or died	Those who were invited in round 4 excluding those who emigrated, actively withdrew from the study or died	Those who were invited in round 5 excluding those who emigrated, actively withdrew from the study or died

^aIn the year 1992, no measurements were carried out: in this year preparation for the next measurement (protocol development) was carried out.

^bOf those participating in round 1, a sample was drawn for round 2.