CORRECTION FOR BIASES IN A POPULATION-BASED STUDY OF FAMILY HISTORY AND CORONARY HEART-DISEASE - THE NEWCASTLE-FAMILY-HISTORY-STUDY-I

In this paper, the authors report on the design of a population-based case-control study of family history as a risk factor for coronary hea rt disease (CHD). They studied the characteristics of subjects who com pleted a detailed family history questionnaire in 1992-1994 as well as the accuracy of recall of family history in order to quantify both se lection and recall biases. Coronary disease cases were enrolled throug h the Newcastle MONICA Project (Monitoring Trends and Determinants in Cardiovascular Disease), which registered all suspected heart attacks and sudden cardiac deaths in the Lower Hunter region of New South Wale s, Australia, between August 1984 and March 1994. Controls were select ed at random from the New South Wales electoral roll. The response rat e was 76% in cases and 62% in controls; the major factor associated wi th participation in the study was perceived family history of CHD, mor e so in the control series than in the case series. Accuracy was deter mined by comparing information obtained from the proband with that rec orded on death certificates. In first-degree relatives, sensitivity of CHD recall was 85% (95% confidence interval (CI) 74-92%) in cases and 95% (95% CI 84-99%) in controls, while specificity was 59% (95% CI 49 -69%) and 74% (95% CI 65-82%), respectively. The net bias in both sele ction and recall is toward the null and hence the comparisons provide a conservative estimate of risk of CHD associated with a positive fami ly history.