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PubMed · 9147604

Comparing two diagnostic tests against the same "gold standard" in the same sample.

D A Bloch
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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.

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AlgorithmsBiometryCase-Control StudiesDiagnostic Tests, RoutineHumansRiskSample SizeSensitivity and SpecificityComparative StudyJournal ArticleResearch Support, U.S. Gov't, P.H.S.

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D A Bloch. 1997. Comparing two diagnostic tests against the same "gold standard" in the same sample.. https://pubmed.ncbi.nlm.nih.gov/9147604/

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