A METHOD FOR COMPARING POSITIVE RATES OF 2 BLOOD CULTURE SYSTEMS

McNemar's test is used to compare two marginal positive rates from an independent-sample of paired binary data. When the pairs are not mutua lly independent, the McNemar's test may not be valid. In this paper, w e propose a random-effects regression model for comparing two marginal probabilities from nonindependent matched pairs data with covariates. An example of comparing positive rates of two blood culture systems i llustrates this method. In this example, there is no external gold sta ndard, the paired data are clustered, the data with negative results f rom both systems are not available, and one culture-specific covariate is involved. The computing method for the maximum likelihood estimati on is efficient.