A positive or a negative confounding variable? A simple teaching aid for clinicians and students

Abla Mehio-Sibai; Manning Feinleib; Tarek A Sibai; Haroutune K Armenian

doi:10.1016/j.annepidem.2004.10.004

A positive or a negative confounding variable? A simple teaching aid for clinicians and students

Ann Epidemiol. 2005 Jul;15(6):421-3. doi: 10.1016/j.annepidem.2004.10.004. Epub 2005 Jan 21.

Authors

Abla Mehio-Sibai¹, Manning Feinleib, Tarek A Sibai, Haroutune K Armenian

Affiliation

¹ Department of Epidemiology and Population Health, Faculty of Health Sciences, American University of Beirut, Beirut, Lebanon. ansibai@aub.edu.lb

PMID: 15967387
DOI: 10.1016/j.annepidem.2004.10.004

Abstract

Anticipating the direction of a confounding variable can be problematic especially to introductory students. Using elementary rules of mathematics, we describe below a simple instructional tool for deriving the direction of confounding bias. The tool is illustrated with examples and a heuristic mathematical justification is also described.

MeSH terms

Bias*
Confounding Factors, Epidemiologic*
Epidemiology / education*
Lebanon
Models, Statistical
Physicians*
Students, Medical*