title: Chance-corrected measures for 2 × 2 tables that coincide with weighted kappa.
abstract: Cohen's kappa is presently a standard tool for the analysis of agreement in a 2 × 2 reliability study, and weighted kappa is a standard statistic for summarizing a 2 × 2 validity study. The special cases of weighted kappa, for example Cohen's kappa, are chance-corrected measures of association. For various measures of 2 × 2 association it has been observed in the literature that, after correction for chance, they coincide with a special case of weighted kappa. This paper presents the general function, linear in both numerator and denominator, that becomes weighted kappa after correction for chance.
authors.affiliation: Leiden University, The Netherlands. warrens@fsw.leidenuniv.nl
authors.forename: Matthijs J
authors.initials: MJ
authors.lastname: Warrens
mesh_terms: D006801:Humans; D015588:Observer Variation; D011581:Psychological Tests / Q000706:statistics & numerical data*; D011594:Psychometrics / Q000706:statistics & numerical data*; D015203:Reproducibility of Results