AU  - Cheng H
TI  - The number needed to be exposed: A potential use for quantifying the strength of an individual risk factor including a protective factor in a cohort study
PT  - JOUR
DP  - 2007
TA  - Archives of Internal Medicine
pages = {1690-1691},
VI  - 167
IP  - 15
AID  - 10.1001/archinte.167.15.1690-a [doi]
4100  - http://dx.doi.org/10.1001/archinte.167.15.1690-a
SO  - Archives of Internal Medicine August 13, 2007 167(15):1690