title: Comparing two diagnostic tests against the same "gold standard" in the same sample.
abstract: Methods are proposed for comparing two diagnostic tests for the same data where a threshold for positive for each test is specified. One method contrasts the diagnostic tests' estimated risks. A second method compares the two tests' kappa coefficients. When thresholds for positive test results are specified a priori, maximum likelihood estimators and their asymptotic variances are derived and test statistics are presented for both case-control and naturalistic methods of sampling. The bootstrap is proposed as a method to assess differences in risk estimators when thresholds for positive test results are chosen by scanning the data. Examples are given to illustrate the methods.
authors.affiliation: Department of Health Research and Policy, Stanford University School of Medicine, California 94305-5092, USA.
authors.forename: D A
authors.initials: DA
authors.lastname: Bloch
mesh_terms: D000465:Algorithms; D001699:Biometry; D016022:Case-Control Studies; D003955:Diagnostic Tests, Routine / Q000592:standards* / Q000706:statistics & numerical data*; D006801:Humans; D012306:Risk; D018401:Sample Size; D012680:Sensitivity and Specificity