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Chapter 8. Cohort Studies
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Which of the following is NOT a feature of a cohort study?
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A. Exposure is determined by randomization.
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B. Exposure level must be assessed.
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C. Subjects are followed for the development of disease.
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D. Risk ratio is a commonly used measure of effect.
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E. It can be used to study either protective or harmful exposures.
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A rate ratio (95% CI) calculated from a cohort study is 1.7 (0.8, 3.4). The most appropriate interpretation is
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A. the exposure is associated with a lower rate and the result is statistically significant.
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B. the exposure is associated with a lower rate, but the result is not statistically significant.
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C. the exposure is associated with increased rate, and the result is statistically significant.
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D. the exposure is associated with increased rate, but the result is not statistically significant.
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Each of the following is a feature of a retrospective cohort study EXCEPT
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A. it is efficient for the study of rare exposures.
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B. information on exposures typically is accurate and complete.
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C. it is efficient for the study of slowly developing diseases.
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D. it typically can be completed more quickly than a prospective cohort study.
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E. it may rely on already collected information.
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Misclassification of disease status, if it is unrelated to exposure, is expected to have what impact on the results of a cohort study?
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A. Result in a reversal of the association of interest
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B. Increase the apparent strength of association
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C. Decrease the apparent strength of association
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D. Impact cannot be predicted
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The null value of the rate ratio is
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If initial exposure status changes during ...