Duke Health - Module 6

Question 1

How serious is the risk of bias?
* Were cases and controls similar with respect to the indication or circumstances that would lead to exposure?
o The characteristics of the cases and controls need to be carefully documented and their — needs to be demonstrated. The choice of comparison groups has a significant influence on the — of the study results. The researchers should identify an appropriate …

Answer 1

similarity
credibility
control population that would be eligible or likely to have the same exposure as the cases.

Question 2

• Were the circumstances and methods for determining exposure similar for cases and controls?
  o In a case control study determination of the — is critical. The exposure in the two groups should be identified by the same method. The identification should avoid any kind of bias, such as — bias. Sometimes using — data, such as medical records, or blinding the interviewer can help eliminate bias.

Answer 2

exposure
recall
objective

Question 3

Odds ratios
* Case control studies are — and can only present results in terms of — NOT —

Answer 3

retrospective
odds
risk

Question 4

Odds ratio

Answer 4

• The odds of previous exposure in a case divided by the odds of exposure in a control patient
• OR = (exposed cases/nonexposed patients) / (exposed controls/not exposed controls)

Question 5

Is there a dose response relationship?

Answer 5

• Having a dose response relationship between exposure and outcome can strengthen association

Question 6

How precise is the estimate of risk?
* To answer this, we look for the …

Answer 6

CI for the odds ratio

Question 7

• Confidence intervals are a measure of the — of the results in a study

Answer 7

precision

Question 8

o Wider intervals indicate — precision
o Narrow intervals show — precision

Answer 8

lower
greater