Bias in methods for deriving standardized morbidity ratio and attributable fraction estimates
Article first published online: 12 OCT 2006
Copyright © 1984 John Wiley & Sons, Ltd.
Statistics in Medicine
Volume 3, Issue 2, pages 131–141, April/June 1984
How to Cite
Greenland, S. (1984), Bias in methods for deriving standardized morbidity ratio and attributable fraction estimates. Statist. Med., 3: 131–141. doi: 10.1002/sim.4780030206
- Issue published online: 12 OCT 2006
- Article first published online: 12 OCT 2006
- Manuscript Revised: NOV 1983
- Manuscript Received: APR 1983
This paper examines several methods for deriving standardized morbidity ratios (SMR) and attributable fraction (attributable risk percentage) estimates. We show that some of the proposed methods will, in general, produce biased estimators, although the low variance of certain estimators sometimes compensates for their bias. A few methods are based on statistical fallacies and should be avoided, especially the method of deriving the expected number of cases from a regression equation that does not include the exposure under study.