申論題

3. Colorectal cancer (CRC) is the third most common cancer worldwide. The performance of guaiac and immunochemical fecal occult blood tests (abbreviated as G-FOBT and FIT, respectively) for the detection of CRC was compared anong 257 asymptomatic and 20 confirmed cancer patients. The results of colonoscopy for all of the 277 subjects were postulated as the gold standard. (Modified from the article: Clin Exp Gastroenterol. 2015； 8: 279-284.)

(B) Colonoscopy was performed to confirm the cancer status for all of the 277 subjects, The results are shown as follows. Calculate sensitivity, specificity, positive predictive value (PPV), and negative predictive values (NPV) of both the G-FOBT and FIT tests. Which test do you think have better performance for CRC screening? (18 marks)