title: A new and improved confidence interval for the Mantel-Haenszel risk difference.
abstract: Writing the variance of the Mantel-Haenszel estimator under the null of homogeneity and inverting the corresponding test, we arrive at an improved confidence interval for the common risk difference in stratified 2 × 2 tables. This interval outperforms a variety of other intervals currently recommended in the literature and implemented in software. We also discuss a score-type confidence interval that allows to incorporate strata/study weights. Both of these intervals work very well under many scenarios common in stratified trials or in a meta-analysis, including situations with a mixture of both small and large strata sample sizes, unbalanced treatment allocation, or rare events. The new interval has the advantage that it is available in closed form with a simple formula. In addition, it applies to matched pairs data. We illustrate the methodology with various stratified clinical trials and a meta-analysis. R code to reproduce all analysis is provided in the Appendix.
authors.affiliation: Department of Mathematics & Statistics, Williams College, Williamstown, MA, U.S.A.
authors.forename: Bernhard
authors.initials: B
authors.lastname: Klingenberg
mesh_terms: D000970:Antineoplastic Agents / Q000627:therapeutic use; D002986:Clinical Trials as Topic; D016001:Confidence Intervals; D003627:Data Interpretation, Statistical; D006801:Humans; D007252:Influenza Vaccines / Q000592:standards; D007251:Influenza, Human / Q000517:prevention & control; D015201:Meta-Analysis as Topic; D009101:Multiple Myeloma / Q000188:drug therapy / Q000401:mortality; D012306:Risk; D018401:Sample Size
chemical_list: D000970:Antineoplastic Agents; D007252:Influenza Vaccines
keywords: difference of proportion; matched pairs; meta-analysis; score interval; stratified 2 × 2 tables