Modeling Agreement between Binary Classifications of Multiple Raters in R and SAS

Modeling Agreement between Binary Classifications of Multiple Raters in R and SAS

Kappa Test for Agreement Between Two Raters

Introduction This module computes power and sample size for the test of agreement between two raters using the kappa statistic. The power calculations are based on the results in Flack, Afifi, Lachenbruch, and Schouten (1988). Calculations are based on ratings for k categories from two raters or judges. You are able to vary category frequencies on a single run of the procedure to analyze a wide...

Estimation of coefficients of individual agreement (CIAs) for quantitative and binary data using SAS and R

The coefficients of individual agreement (CIAs), which are based on the ratio of the intra- and inter-observer disagreement, provide a general approach for evaluating agreement between two fixed methods of measurements or human observers. In this paper, programs in both SAS and R are presented for estimation of the CIAs between two observers with quantitative or binary measurements. A detailed ...

Kappa Statistics for Multiple Raters Using Categorical Classifications

In order to assess the reliability of a given characterization of a subject it is often necessary to obtain multiple readings, usually but not always from different individuals or raters. The degree of agreement among the various raters gives some indication as to the consistency of the values. If agreement is high, we feel more confident the ratings reflect the actual circumstance. If agreemen...

A-Kappa: A measure of Agreement among Multiple Raters

Abstract: Medical data and biomedical studies are often imbalanced with a majority of observations coming from healthy or normal subjects. In the presence of such imbalances, agreement among multiple raters based on Fleiss’ Kappa (FK) produces counterintuitive results. Simulations suggest that the degree of FK’s misrepresentation of the observed agreement may be directly related to the degree o...