1. Koch to Quantiferon: An Overview of Tuberculosis testing in the United States Jamie Ritchey, MPH April 28, 2008 EPID 755: Emerging Infectious Diseases
2.
3.
4.
5.
6.
7.
8.
9.
10. Tuberculin skin test Specificity: False positive test results ***Lowers the NPV, specificity, and sensitivity Specificity 182 / 200= 91% 2 / 200= 1% Sensitivity 2/3= 66.7% Total NPV 182/183= 99.5% 2 / 3= 66.7% True negative 182 180 2 False negative 1 Negative PPV = 10% 2 / 200= 1% False positive 18 180 198 True positive 2 Positive Predictive Value False True Test Result
11.
12. Tuberculin skin test Sensitivity: inability to mount an immune response (HIV +, malnutrition, chemo) **False negative results cause a drop in sensitivity, PPV and NPV Specificity 182 / 200= 91% Sensitivity 2/3= 66.7% 1/3= 33.3% Total NPV 182/183= 99.5% 182/184= 98.9% True negative 182 False negative 1 1 2 Negative PPV 2/18= 10% 1/18= 5.6% False positive 18 True positive 2 1 Positive Predictive Value False True Test Result