title: Attributable risk ratio estimation from matched-pairs case-control data.
abstract: Explicit formulas are provided for estimating the attributable risk ratio among the exposed and the entire target population utilizing matched-pairs data. Large-sample standard errors and corresponding confidence intervals are provided. These estimates can be obtained from the cross-classification frequencies of matched pairs by disease and exposure status in the usual 2 X 2 table. The key to the development of these formulas lies in recognizing that attributable risk among the exposed is a direct function of the odds ratio, and population attributable risk is a direct function of the odds ratio and exposure prevalence among only the cases (assuming a rare disease). The formulas presented in this paper require only a calculator for computation. The methodology is illustrated with data from a matched-pairs case-control study of oral conjugated estrogens and endometrial cancer.
mesh_terms: D003276:Contraceptives, Oral / Q000009:adverse effects; D004812:Epidemiologic Methods; D005260:Female; D006801:Humans; D012189:Retrospective Studies; D013223:Statistics as Topic; D014594:Uterine Neoplasms / Q000139:chemically induced
chemical_list: D003276:Contraceptives, Oral