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A modified large-sample approach to approximate interval estimation for a particular intraclass correlation coefficient.

Joseph C Cappelleri·Naitee Ting
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Abstract

We consider the problem of constructing a confidence interval for the intraclass correlation coefficient in an interrater reliability study when both raters and subjects are random effects in a two-way random effects model. A simulation study is conducted to investigate and compare the interval coverage per cents of three methods of approximation: (i) Satterthwaite's two moments, the standard approach; (ii) modified three moments, a newer approach; and (iii) modified large sample, the newest approach for this particular problem. One-sided lower and two-sided bounds are examined. For the two-moment approach, coverage of confidence intervals can be understated for not only one-sided bounds but also two-sided bounds. Coverage of confidence intervals for the modified large-sample approach is either correct or conservative and provides narrower two-sided widths than the modified three-moment approach, which can understate coverage on one-sided and two-sided bounds for two or three raters. The competing methods are illustrated with data from a reliability study of four raters evaluating the number of decayed, missing, and filled surfaces in the permanent teeth of ten subjects. Overall, the modified large-sample approach provides the most satisfactory performance of the three methods.

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Clinical Trials as TopicConfidence IntervalsHumansModels, StatisticalMonte Carlo MethodObserver VariationProbabilityReproducibility of ResultsSample SizeTooth DiseasesUnited StatesJournal Article

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Joseph C Cappelleri, Naitee Ting. 2003-06-15. A modified large-sample approach to approximate interval estimation for a particular intraclass correlation coefficient.. https://doi.org/10.1002/sim.1402

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