The Effects of Misclassification on the Bias in the Difference between Two Proportions and the Relative Odds in the Fourfold Table

Abstract

It is shown elsewhere [15] that the false negative and false positive rates associated with medical screening techniques do not follow any general or simple models; and that the usual assumptions made for analytical purposes are violated. The effects of reasonable and actual levels of misclassification in the 2 × 2 table on the bias in the difference between two proportions and on the bias in relative odds as well as on the distributions of these statistics are examined. The false positive rates, and in particular the difference between them, in the two sample problem are responsible for most of the bias resulting from misclassification.