Organizational and methodological aspects of enrollment of the population cohorts for preventive studies

An analysis is presented of the organizational and methodical aspects of the enrollment of a proband cohort for preventive studies, and of the tests for its representativity and comparability. The methods are described that had been applied in the enrollment of probands for participation in the Kaunas - Rotterdam methodological study of ischaemic heart disease, and the causes of non-participation in the study are classified.