Question 7 In a large case-control study of patients with pancreatic cancer, 17% of the patients were found to be diabetic at the time of diagnosis, compared to 4% of a well-matched control x group (matched by age, sex, ethnic group, and several other characteristics) that was examined for diabetes at the same time as the cases were diagnosed. It was concluded that the diabetes played a causal role in the pancreatic cancer. This conclusion: Selected Answer: D. May be incorrect because of less complete ascertainment of diabetes in the pancreatic cancer cases Answers: A. Is correct B. May be incorrect because there is no control or comparison group c. May be incorrect because of failure to establish the time sequence between onset of the diabetes and diagnosis of pancreatic cancer D. May be incorrect because of less complete ascertainment of diabetes in the pancreatic cancer cases E. May be incorrect because of more complete ascertainment of pancreatic cancer in nondiabetic personsQuestion 10 You are designing a case control study of 100 men with prostate cancer. What is the ONE essential prerequisite of the control group? X Selected Answer: B. Controls should be from hospital settings but should be subsets of many different diagnostic categories. Answers: A. The controls should be from both hospital and community settings. B. Controls should be from hospital settings but should be subsets of many different diagnostic categories. C. Controls should be matched to eliminate confounders. D. Controls should be free from prostate cancer. Question 11 In the individually matched (1 to 1 or pair matching) case-controlled study, the only pairs that contribute to the odds ratio in a matched analysis are those in which the: X Selected Answer: C. Exposure status is the same for members of the pair Answers: A. Exposures status is different between the members of the pair B. Disease status is different between members of the pair c. Exposure status is the same for members of the pair D. Disease status is the same for members of the pairQuestion 15 Lymphosarcoma is extremely rare. Risk factors for the disease are largely unknown. What kind of study would be most appropriate for investigating risk factors of lymphosarcoma? X Selected Answer: A. Experimental study Answers: A. Experimental study B. Historical (retrospective) cohort study C. Prospective cohort study D. Case-control study E. Double-blind randomized clinical trialQuestion 5 In a case-control study of the relationship between myocardial infarction (MI) and recent oral contraceptive (OC) use, Shapiro et al. reported the following data: 29 OC users with MI; * 205 non-OC users with MI; 135 OC users with no MI; 1607 non-OC users with no MI. The correct interpretation of this odds ratio (OC use is the exposure) is: (hint: you need to create a 2 X 2 table here. Put cases and controls in columns) Selected Answer: OC users are 1.57 times more likely to have myocardial infarction than non-OC users A. Answers: OC users are 1.57 times more likely to have myocardial infarction than non-OC users A. B. OC users are 8.41 times more likely to have myocardial infarction than non-OC users. c. OC users are .32 times more likely to have myocardial infarction than non-OC users. D. The odds of OC use in cases with MI is 1.68 times that observed for controls without MI. Question 6 In a case-control study, which of the following is true? X Selected Answer: E. All of the above Answers: A. The proportion of cases with the exposure is compared with the proportion of controls with the exposure B. Disease rates are compared for people with the factor of interest and for people without the factor of interest c. The investigator may choose to have multiple comparison groups D. A and C E. All of the above