This Article Full Text (PDF) References Alert me when this article is cited Alert me if a correction is posted Citation Map Services Email this article to a friend Similar articles in this journal Similar articles in PubMed Alert me to new issues of the journal Add to Saved Citations Download to citation manager Request Permissions Request Reprints Add to My Marked Citations Google Scholar Articles by Metcalfe, C. Articles by Hart, C. L. PubMed PubMed Citation Articles by Metcalfe, C. Articles by Hart, C. L. Social Bookmarking                   What's this?

The scope for biased recall of risk-factor exposure in case-control studies: Evidence from a cohort study of Scottish men

Department of Social Medicine, University of Bristol, Bristol, UK, chris.metcalfe{at}bristol.ac.uk

John Macleod

Department of Social Medicine, University of Bristol, Bristol, UK

George Davey Smith

Department of Social Medicine, University of Bristol, Bristol, UK,

Carole L. Hart

Public Health and Health Policy, Division of Community Based Sciences, University of Glasgow, Glasgow, UK

Aims: Case-control studies are prone to recall bias, a participant's case-control status influencing their recall of exposure to risk factors. We aimed to demonstrate empirically the scope for this bias. Methods: Two thousand five hundred and fifty men without coronary heart disease at enrolment to a prospective cohort study underwent two health assessments, about 5 years apart. The association between the development of coronary heart disease in the intervening period and changes in reported stress and cigarette smoking were investigated. Results: Men admitted to hospital with coronary heart disease reported a greater increase in psychological stress (p=0.032) and greater cessation of smoking (22% vs. 10%; p=0.007) than men not admitted. Consequently, when exposure data are collected at the end rather than at the start of the follow-up period, coronary heart disease is observed to be more strongly associated with psychological stress, and more weakly associated with smoking. Conclusions: At the time when a case-control study is conducted, levels of exposure to risk factors will have been influenced by disease development. When participants are asked about their level of exposure for a previous time period, recall is likely to be influenced by present outcome and exposure status, especially when psychological states are being investigated.

Key Words: Bias (epidemiology) • case-control studies • coronary disease • psychological stress • risk factors • smoking

CiteULike    Connotea    Del.icio.us    Digg    Reddit    Technorati    What's this?