Posted: February 24th, 2017

What type of measure of association should the investigators calculate? (2 pts) A. Odds ratio B. Prevalence C. Case-fatality rate D. Prevalence ratio E. Relative risk

Disease-specific mortality rates can give a good estimate of the incidence of the disease when the following condition is true: (3 pts) A. The prevalence of the disease is high and duration of disease is short B. The incidence of the disease is high and duration of disease is short C. The mortality rates are age-adjusted D. The case-fatality rate is high and the duration of disease is short E. The crude mortality rate equals the age-adjusted mortality rate

16. The strength of an association is one of the criteria for evaluating the cause and effect relationship between an exposure and outcome. Which of the following is a measure of the strength of association? (2 pts) A. Incidence rate among the exposed B. Cumulative incidence among the exposed C. The ratio of odds of exposure among cases to the odds of exposure among the non-cases D. Odds of disease among exposed relative to the prevalence of exposure in the source population E. None of the above

17. In 2002, investigators started a study of the association of cholesterol levels and stroke in a group of 2,000 healthy persons who had participated in a cholesterol screening program in 1992. The investigators determined exposure categories using cholesterol levels in all persons that were measured at the time of the screening program. A cut-off value of 200 mg/dL was used to define ‘high’ cholesterol while those with levels below 200 were identified as having ‘low’ cholesterol. Using this definition, 1,000 persons had ‘high’ cholesterol levels while the remaining 1,000 persons had ‘low’ cholesterol. The investigators then ascertained whether these originally healthy persons had experienced a stroke. They determined that 150 cases of stroke occurred by the end of 2002, with 113 cases occurring in the high cholesterol group.

a. What is the study design that the investigators used? (2 pts) A. Case-control study B. Retrospective cohort study C. Prospective cohort study D. Cross-sectional study E. Randomized clinical trial

b. What type of measure of association should the investigators calculate? (2 pts) A. Odds ratio B. Prevalence C. Case-fatality rate D. Prevalence ratio E. Relative risk

c. Using the reported study data, what is the association measure that should be calculated? (3 pts) A. 3.1 B. 3.3 C. 67% D. 1.0 E. 0.3