title: Statistical inference of risk difference in K correlated 2 x 2 tables with structural zero.
abstract: K correlated 2 x 2 tables with structural zero are commonly encountered in infectious disease studies. A hypothesis test for risk difference is considered in K independent 2 x 2 tables with structural zero in this paper. Score statistic, likelihood ratio statistic and Wald-type statistic are proposed to test the hypothesis on the basis of stratified data and pooled data. Sample size formulae are derived for controlling a pre-specified power or a pre-determined confidence interval width. Our empirical results show that score statistic and likelihood ratio statistic behave better than Wald-type statistic in terms of type I error rate and coverage probability, sample sizes based on stratified test are smaller than those based on the pooled test in the same design. A real example is used to illustrate the proposed methodologies.
authors.affiliation: Department of Statistics, Yunnan University, Kunming 650091, People's Republic of China.
authors.forename: Shun-Fang
authors.initials: SF
authors.lastname: Wang
authors.forename: Nian-Sheng
authors.initials: NS
authors.lastname: Tang
authors.forename: Bo
authors.initials: B
authors.lastname: Zhang
authors.forename: Xue-Ren
authors.initials: XR
authors.lastname: Wang
mesh_terms: D056808:Biostatistics / Q000379:methods*; D003198:Computer Simulation / Q000706:statistics & numerical data; D016001:Confidence Intervals; D015233:Models, Statistical; D018570:Risk Assessment / Q000379:methods*; D018401:Sample Size