title: Confidence intervals of effect size for paired studies.
abstract: To construct a confidence interval of effect size in paired studies, we propose four approximate methods--Wald method, variance-stabilizing transformation method, and signed and modified signed log-likelihood ratio methods. We compare these methods using simulation to determine those that have good performance in terms of coverage probability. In particular, simulations show that the modified signed log-likelihood ratio method produces a confidence interval with a nearly exact coverage probability and highly accurate and symmetric error probabilities even for very small samples. We apply the methods to data from an iron deficiency anemia study.
authors.affiliation: Department of Biostatistics, St Jude Children's Research Hospital, 332 North Lauderdale St., Memphis, TN 38105, USA. jianrong.wu@stjude.org
authors.forename: Jianrong
authors.initials: J
authors.lastname: Wu
authors.forename: Guoyong
authors.initials: G
authors.lastname: Jiang
mesh_terms: D001699:Biometry / Q000379:methods*; D003198:Computer Simulation; D016001:Confidence Intervals; D003627:Data Interpretation, Statistical; D015233:Models, Statistical