Sensitivity, Specificity, and Predictive Value

Yerushalmy’s pioneering work1 on observer variability in the interpretation of chest roentgenograms initiated a still-expanding interest in the evaluation of the diagnostic process. He introduced the terms sensitivity and specificity as measures of the validity of diagnostic tests, and an entire methodology including the concept of predictive value has developed in response to the geometric growth in and reliance on diagnostic testing in clinical practice.