Cardiovascular diseases and risk factors in a population-based study in The Netherlands: agreement between...

Since 1987 the Monitoring Project on Cardiovascular Risk Factors has been carried out in The Netherlands. The purpose of the present study was to assess the agreement between the self-reported questionnaire information that was collected in this survey on cardiovascular diseases and risk factors and information from medical records.

From 1987 to 1991, over 36,000 men and women aged 20-59 years have participated in the Monitoring Project on Cardiovascular Disease Risk Factors, a cross-sectional population-based study. We compared self-reported information on cardiovascular diseases and risk factors with the general practitioners medical records from a sample of 899 hypertensive subjects.

The highest proportion of positive self-reports could be confirmed by the medical records for diabetes conditional on self-report of medication use for this condition (100%), and a history of hypertension conditional on the presence of blood pressure recordings in the medical records (91%). The lowest percentage of positive self-reports confirmed by medical records was a family history of myocardial infarction (3-5%). More than 80% of the negative self-reports were confirmed by the medical records for most conditions, except for history of hypertension, conditional on the presence of blood pressure recordings in the medical records (40%). The overall agreement above chance was substantial for cerebrovascular disease (kappa = 0.78) and diabetes (kappa = 0.75), moderate for myocardial infarction (kappa = 0.55), poor for myocardial infarction of the respondents' father (kappa = 0.07) and mother (kappa = 0.05), and fair to moderate for all other self-reported conditions.

Agreement between self-reported information and medical records was variable. For further studies, self-reports of cardiovascular diseases and risk factors should preferably be complemented with information from other sources such as medical records.