title: Adjusted inference procedures for the interobserver agreement in twin studies.
abstract: We propose adjusted inference procedures for evaluating the agreement/disagreement of two raters in a clustered setting involving twins or paired body parts. These procedures include the construction of a confidence interval for the kappa statistic, a related test of statistical significance and a formula that facilitates sample size estimation. The results of a simulation study suggest that a simple adjustment using an estimated design effect will provide valid inferences. The methods proposed are illustrated using an example from the literature.
authors.affiliation: Department of Epidemiology and Biostatistics, Western University, London, ON, Canada Division of Nephrology, Department of Medicine, London Health Science Centre and Western University, London, ON, Canada Stephanie.dixon@lhsc.on.ca.
authors.forename: Stephanie N
authors.initials: SN
authors.lastname: Dixon
authors.affiliation: Department of Epidemiology and Biostatistics, Western University, London, ON, Canada.
authors.forename: Allan
authors.initials: A
authors.lastname: Donner
authors.affiliation: Department of Epidemiology and Biostatistics, Western University, London, ON, Canada Department of Scientific Computing, King Faisal Specialist Hospital and Research Centre, Riyadh, Kingdom of Saudi Arabia.
authors.forename: Mohamed M
authors.initials: MM
authors.lastname: Shoukri
mesh_terms: D016001:Confidence Intervals; D005260:Female; D006801:Humans; D008327:Mammography / Q000379:methods*; D015233:Models, Statistical; D015588:Observer Variation; D015203:Reproducibility of Results; D012107:Research Design; D018401:Sample Size; D018433:Twin Studies as Topic / Q000379:methods*
keywords: Paired data; confidence interval construction; goodness-of-fit significance test; kappa statistic; sample size estimation