This paper proposes and develops a modified expression for relative risk that structurally reflects in its formulation the prevalence rate, the proportion of the population expected to test positive to the condition and the false rates of the test for use in the evaluation of diagnostic screening test results and as measure of association between test results and state of nature or condition in a population, that is different from the method traditionally used in the estimation of relative risks. The method enables the estimation of not only the proportion of the population expected to respond positive in the screening test but also the sensitivity, specificity, false positive rate and false negative rate of the test which provide additional useful information over and above the traditional method of estimating relative risks. Estimate of the standard error of the proposed measure and chi-square test statistic for testing the statistical significance of the estimated relative risk are developed in terms of the estimated sensitivity and specificity of the screening test. The sample data used for illustration indicate that the proposed modified relative risk is likely to be a better measure of association between screening test results and state of nature or condition in a population in comparison with the traditional measure of relative risk.
Download Full Page
<<< Go Back