© 1998 Oxford University Press
research-article |
A methodological note on the selection of friends as controls
Department of Clinical Epidemiology, Chaim Sheba Medical Center, and the Stanley Steyer Institute for Cancer Epidemiology and Research, Tel Aviv university Tel Hashomer, Israel
Reprint requests: Dr Baruch Modan, Department of Clinical Epidemiology. Chalm Sheba Medical Center, Tel Hashomer, 52621, Israel
A number of issues inherent in the selection of friends as controls in case-control studies are illustrated in the light of a recent dietary study, based on hospital and friend controls. Preselection of certain characteristics of the controls by the interviewee is almost unavoidable. The choice of controls to be used in a case-control study must reflect the nature and type of hypothesis which is bemg tested. Advantages and drawbacks of potential control groups must be weighted against each other.
Keywords Case control studies, controls, friends, N-nitroso compounds, brain tumours
Accepted 28 November 1997