A general caxedorical data memddology for evaluating medical diagnostic tests
Measures of sensitivity, predictive accuracy, and agreement are currently used to evaluate the efficiency of diagnostic tests reported on dichotomous scales. This paper presents a unified approach to the evaluation of diagnostic tests in terns of generalized Lnuices of sensitivity, misclassification, predictive accuracy and inaccuracy, classification agreement and prediction agreement for polytomous measurement scales. It Is sufficiently general to accommodate additional complications of study design factors such as multiple testing, known and unknown disease prevalence distributions, and multiple subpopulations defined by the cross-classification of independent factors. Estimation and hypothesis testing are developed within a general linear models approach to the analysis of categorical data from repeated measurement lesigns using weighted least squares computations. This methodology is illustrated within the context of data from a. large cotmiunity-based epidemiologic study of obstructive airways diseas...