Tuberculosis screening.

Abstract

In view of the decreasing prevalence of tuberculosis, it is important to be aware of the factors influencing the sensitivity, specificity and predictive value of tuberculin testing. The small predictive value of tuberculin testing in a low-risk population makes it an ineffective means for screening. Even in high-risk populations, factors such as geographic location, reaction size, previous skin testing and BCG vaccination significantly influence interpretation of the skin test.