Deck 8: Experimental Studies in Epidemiology

Question 1

Experimental studies involving randomization are always preferred over nonrandomized studies.

Answer 1

False

Question 2

A factorial design may be useful for all of the following reasons, EXCEPT:

A) allows testing of a less-mature hypothesis along with a more mature hypothesis.
B) allows one to answer two or more questions in a single study.
C) reduce cost.
D) reduce feasibility.

Answer 2

D

Question 3

Which of the following designs is potentially most useful for making a judgment about causality?

A) Cross-sectional
B) Case-control
C) Case series
D) Experimental

Answer 3

D

Question 4

Selection of a high-risk population of developing the outcomes of interest is a primary strategy to ensure the accumulation of an adequate number of cases that will develop the end point(s).

Question 5

What effect does randomization in a large intervention study have?

A) Minimizes bias in the observation of outcomes of interest
B) Minimizes potential bias in the allocation of participants to treatment group
C) Both A and B are correct.
D) Neither A nor B is correct.

Question 6

What is a limitation of using a run-in period in an intervention study?

A) The study subjects may differ from the general population.
B) Compliance
C) Loss to follow-up
D) All of these are limitations.

Question 7

Which choice best match the following description:
-Investigation of the effectiveness of the poliomyelitis vaccine

A) therapeutic trial
B) prophylactic trial

Question 8

Which choice best match the following description:
-Assessment of the effectiveness of radiation versus surgery in prostate cancer patients

A) therapeutic trial
B) prophylactic trial

Question 9

Was the Tuskegee syphilis study an experimental study?

Question 10

The experimental study is effective when the outcome of interest is rare.

Question 11

The __________ is defined as the effect on patient outcomes that may occur due to the expectation by a patient that a particular intervention will have an effect.

A) interviewer effect
B) recall effect
C) selection effect
D) placebo effect

Question 12

The within-group design provides less control over confounders than the between-group design.

Question 13

An unplanned type of experimental study where the levels of exposure to a presumed cause differ among a population in a way that is relatively unaffected by extraneous factors, such that the situation resembles a planned experiment, is called:

A) a nonrandomized experiment.
B) a natural experiment.
C) a placebo-controlled experiment.
D) All of these are correct.

Question 14

Underlying the estimation of sample size are all of the following, EXCEPT:

A) formulation of the null and one- or two-tailed research hypothesis.
B) the appropriate statistical test.
C) α and β.
D) All of these are involved in sample size estimation.

Question 15

Surrogate endpoints become particularly useful in randomized controlled trials when the outcome phenomenon of interest is common.

Question 16

Which of the following is NOT associated with a Phase II trial?

A) Fewer than 50 patients
B) Randomization
C) Tests side effects
D) Tests tolerability