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Stratification for confounding--part 1: the Mantel-Haenszel formula

Giovanni Tripepi1, Kitty J Jager, Friedo W Dekker

  • 1CNR-IBIM, Clinical Epidemiology and Physiopathology of Renal Diseases and Hypertension of Reggio Calabria, Reggio Calabria, Italy. gtripepi@ibim.cnr.it

Nephron. Clinical Practice
|July 29, 2010
PubMed
Summary

Stratification controls confounding by creating subgroups. The Mantel-Haenszel formula combines stratum-specific relative risks (RR) or odds ratios (OR) for unconfounded effect estimates in observational studies.

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