Epi Ch. 9 And 10 Quiz

Front 1

The population etiologic fraction is a measureof the proportion of the disease rate in a population attributable to theexposure of interest. This measure of effect is influenced by:

Back 1

A. therelative risk of the disease in exposed individuals versus unexposedindividuals.

A. theprevalence of the exposure in the population.

Front 2

The population etiologic fraction for aparticular disease from Factor X alone is five times greater than that fromFactor Y alone. If the relative risk associated with Factor X is 2, and withFactor Y is 20, which of the following statements is true?

Back 2

Fewerpersons are exposed to Factor Y than to Factor X

Front 3

Thedeath rate per 100,000 for lung cancer is 7 among non-smokers and 71 amongsmokers. The death rate per 100,000 for coronary thrombosis is 422 amongnon-smokers and 599 among smokers. The prevalence of smoking in the populationis 55%.

Back 3

* D. 10.1 for lung cancer and 1.4 for coronary thrombosis.

Front 4

8. The population etiologic fraction ofdisease due to smoking is:

Back 4

D. 0.83 for lung cancer and0.18 for coronary thrombosis.

Front 5

On the basis of the relative risk and etiologicfractions associated with smoking for lung cancer and coronary thrombosis,which of the following statements is most likely to be correct?

Back 5

Smokingseems much more likely to be causally related to lung cancer than to coronary thrombosis

Front 6

If it is accepted that an observed associationis a causal one, an estimate of the impact that a successful preventive programmight have can be derived from

Back 6

attributable risk

Front 7

A causal association between factor and outcomecan refer to:

Back 7

Indirect association

Directassociation

Front 8

In a study to determine the incidence of achronic disease, 150 people were examined at the end of a three-year period.Twelve cases were found, giving a cumulative risk of 8%. Fifty other members ofthe initial cohort could not be examined; 20 of these 50 could not be examinedbecause they died. Which source of bias may have affected the study?

Back 8

Selectionbias: survival bias

Front 9

You are investigating the role of physicalactivity in heart disease and suggest that physical activity protects against havinga heart attack. While presenting these data to your colleagues, someone asks ifyou have thought about confounders such as factor X. This factor X could haveconfounded your interpretation of the data if it

Back 9

isa factor associated with physical activity and heart disease.

Front 10

The strategy which is not aimedat reducing selection bias is:

Back 10

standardizedprotocol for structured interviews

Front 11

methodfor controlling the effects of confounding in epidemiologic studies?

Back 11

Randomization B. Stratification C. Matching

E. Restriction

Front 12

The purpose of a double-blind study is to:

Back 12

avoidobserver and interviewee bias.

Front 13

In a survey which uses lay interviewers tointerview one person about his or her health and the health of householdmembers, the sources of error include:

Back 13

theperson with disease has had no symptoms and is not aware of the disease.B. the respondent provides the informationbut the interviewer doesn’t record it or records it incorrectly.C. the interviewer doesn’t ask thequestions that he or she is instructed to ask, or asks them incorrectly.D. the person has had symptoms and has hadmedical attention but does not know the name of the disease.

Front 14

An epidemiologic experiment is performed inwhich one group is exposed to a suspected factor and theother is not. All individuals with an odd hospital admission number are assignedto the second group. The main purpose of this procedure is to:

Back 14

A. improvethe likelihood that the two groups will be comparable with regard to known andunknown confounding factors.

Front 15

20. Adouble-blind study of a vaccine is one in which:

Back 15

neitherobservers nor subjects know which subject receives the vaccine and whichreceives a placebo