Deck 11: Confounding

Question 1

Which of the following can be thought of as a failure of the comparison group to reflect the counterfactual experience of the exposed group?

A) Bias
B) Confounding
C) Random error
D) Generalization

Answer 1

Confounding

Question 2

Which of the following tools is a visual representation of the relationship between a confounder, the exposure, and the disease?

A) Histogram
B) Decision tree
C) Infographic
D) Directed acyclic graph

Answer 2

Directed acyclic graph

Question 3

Which type of studies do not suffer from confounding by severity mainly because randomization balances the severity distribution of the compared groups?

A) Cohort studies
B) Etiologic studies
C) Experimental studies
D) Case-control studies

Answer 3

Experimental studies

Question 4

Epidemiologists typically determine which variables are potential confounders by conducting which of the following to ascertain all currently known risk factors for the disease under study?

A) Meta-analysis
B) Restriction
C) Randomization
D) Literature review

Question 5

Which of the following ensures that the treatment assignment occurs in an unbiased fashion and will on average result in a balanced distribution of both known and unknown confounders if the sample size is large enough?

A) Matching
B) Restriction
C) Randomization
D) Literature review

Question 6

Which of the following means that investigators select the study subjects so that potential confounders are distributed in an identical manner?

A) Matching
B) Restriction
C) Randomization
D) Literature review

Question 7

Epidemiologists commonly use which of the following to control for demographic variables such as age, race, gender, and calendar time?

A) Matching
B) Restriction
C) Randomization
D) Standardization

Question 8

The confounding variable must be more or less common in the comparison group than in the exposed group.

Question 9

Confounding is an all-or-none condition described merely by its presence or absence.

Question 10

Confounding by severity in observational studies usually makes the therapy appear less effective than it appeared in experimental studies.

Question 11

The mixing of effects between an exposure, an outcome, and a third extraneous variable is referred to as which of the following?

A) Bias
B) Confounding
C) Blocking
D) Matching

Question 12

Except for which of the following, it is impossible to control for a confounder without data?

A) Matching
B) Restriction
C) Randomization
D) Standardization

Question 13

If the true risk ratio is 1.0 and the confounded risk ratio is 2.0, this is an example of which of the following?

A) Positive confounding
B) Negative confounding
C) Confounding by indication
D) Confounding by severity

Question 14

Which of the following occurs when individuals who are treated for their condition are compared with individuals who have neither the condition nor the treatment?

A) Positive confounding
B) Negative confounding
C) Confounding by indication
D) Confounding by severity

Question 15

If which of the following occurs in observational studies, it usually makes the therapy appear less effective than it appeared in experimental studies?

A) Positive confounding
B) Negative confounding
C) Confounding by indication
D) Confounding by severity

Question 16

If investigators use which of the following to control for confounding in the design phase, this means that admissibility criteria for study subjects is limited?

A) Matching
B) Restriction
C) Randomization
D) Standardization

Question 17

Which of the following is needed when the confounder is a complex nominal variable, such as occupation, neighborhood, or familial characteristic such as sibship?

A) Matching
B) Restriction
C) Randomization
D) Standardization

Question 18

Epidemiological studies of the relationship between an exposure and a disease are susceptible to the disturbing influences of extraneous factors called confounders.

Question 19

Confounding can be thought of as a failure of the exposed group to reflect the counterfactual experience of the comparison group.

Question 20

A confounding variable can be an intermediate step in the causal pathway between the exposure and the disease.