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The article has addressed a very important concept of screening tests' validity & its contextual use in populations. Positive and negative likelihood ratio are explained and displayed well in relation to prevalence of disease. It would have been more comprehensive, had the authors explained both pre-test and post-test probabilities of screening test by using a likelihood ratio Nomogram. Furthermore, "Yield" of the screening test was also to be discussed to encompass all features of screening test.
The article rightly identified that Primary care practice can be made more useful to advocate informed choices by focusing on likelihood ratio of these screening tests rather than predictive positive or negative values in different populations.