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A confidence interval approach to sample size estimation for interobserver agreement studies with multiple raters and
Michael A Rotondi1, Allan Donner
1School of Kinesiology and Health Sciences, York University, Room 364, Norman Bethune College, 4700 Keele Street, Toronto, Ontario, Canada M3J 1P3. mrotondi@yorku.ca
Journal of Clinical Epidemiology
|May 8, 2012
Summary
Researchers developed a new sample size estimation technique for interobserver agreement studies. This method helps achieve precise estimates of the kappa coefficient, improving study design in various clinical fields.
Area of Science:
- Medical Statistics
- Clinical Research Methodology
Background:
- Interobserver agreement studies are prevalent in clinical practice.
- Sample size estimation for these studies is often underdeveloped compared to clinical trials.
Purpose of the Study:
- To propose a novel sample size estimation technique for interobserver agreement studies.
- To enable the achievement of prespecified confidence interval limits for the kappa coefficient.
Main Methods:
- The technique accommodates any number of outcomes and raters.
- It is applicable across diverse fields like pathology, psychiatry, dentistry, and physical therapy.
Main Results:
- The method was illustrated with examples from oral radiology (mandibular cortical index) and nursing (triage levels).
- These examples demonstrate the practical application of the sample size technique.
Conclusions:
- The proposed method aids in planning interobserver agreement studies requiring specific precision for kappa coefficient estimation.
- An R software package, kappaSize, is available to implement this technique.
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