To evaluate the accuracy of antibody (IgG, IgM) rapid testing as a screening test for Covid19, 246 individuals showing symptoms of dry cough, fever and sore throat were the subjects of the study. Out of the 246 symptomatic individuals, 189 tested positive for RT PCR which is currently the gold standard for COVID19 confirmatory testing. However, only 115 tested reactive for the antibody rapid testing while 74 tested non-reactive. With these data at hand, compute for the following:

a) Sensitivity of antibody rapid testing as a screening test for COVID19. Interpret the value obtained. (2pts) b) Specificity of antibody rapid testing as a screening test for COVID19. Interpret the value obtained. (2pts) c) Positive Predictive Value (PPV) of antibody rapid testing as a screening test for COVID19. Interpret the value obtained (2pts) d) Negative Predictive Value (NPV) of antibody rapid testing as a screening test for COVID19. Interpret the value obtained (2pts) *Create and label your own contingency table reflecting the data presented above. (12pts)