Posted: October 3rd, 2016

Recall bias is minimized compared with a case-control study

10. Colon cancer is diagnosed in 45 patients per year within a community of 10,000 unaffected individuals. A screening test is applied to all residents of this community.
• What is the sensitivity (in %) of the screening test, if it detects 38 of the colon cancer patients. What is the specificity if the test correctly determines that 9,750 of the unaffected persons who do not have colon cancer? What is the positive predictive value? What is the negative predictive value
[Interpret the results and show your calculations for full credit].
a. The sensitivity of the test is [ONE POINT]_____________
b. The specificity of the test is [ONE POINT] ______
c. The positive predictive value of the test is [ONE POINT] _____________
d. The negative predictive value of the test is [ONE POINT] ____________
e. What are your overall comments about the validity of this test? [ONE POINT]
11. Which of the following is not an advantage of a prospective cohort study? [ONE POINT]

a. Precise measurement of exposure is possible
b. Incidence rates can be calculated
c. It usually costs less than a case-control study
d. Recall bias is minimized compared with a case-control study
e. Many disease outcomes can be studied simultaneously