EBM MULTIPLE CHOICE QUESTIONS
Subjects serve as their own controls in which of the following research design?
a. Factorial design
b. Parallel design
c. Cross‐over design
d. Randomized control trial
e. Case‐control study - Answers :c. Cross‐over design
The most effective method of controlling extraneous variables is by:
a. Analysis of covariance
b. Matching
c. Randomization
d. Use control group
e. None of the above - Answers :c. Randomization
A study is conducted to determine the efficacy of 2 drugs in preventing seasickness.
Measurements are taken to assess the following: no seasickness, mild seasickness,
or severe seasickness. Which of the following data types best describes these
measurements?
a. Nominal
b. Ordinal
c. Interval
d. Ratio
e. Integer - Answers :b. Ordinal
Which of the following best describes the function of the inclusion criteria for a study?
a. Assures patient safety
b. Describes the characteristics of the sample
c. Is important in evaluating the external validity of the study
d. B and C
e. None of the above - Answers :d. B and C
A study is conducted to determine the effect of Vitamin C tablets on mortality. After the
study is completed, the data indicate that patients taking Vitamin C tablets had a
decrease in mortality. However, the study design did not control for the effects of dietary
Vitamin C. Which of the following terms best describes the role of DIETARY Vitamin C
in this study?
a. Independent variable
b. Dependent variable
c. Confounding variable
d. Control variable
,e. None of the above - Answers :c. Confounding variable
In some non‐randomized studies, patients are assigned to certain treatment groups
based on some characteristic that they possess, which could affect the outcome of the
study. This type of bias is known as:
a. Volunteer bias
b. Contamination bias
c. Selection bias
d. Correlation bias
e. None of the above - Answers :c. Selection bias
One of the main limitations of a cross‐over design in drug studies in humans is:
a. The study is conducted during a specified time "window"
b. Requires a washout period to remove any residual effects from previous drug
treatments
c. If a drug induces a permanent effect (i.e. antibiotic cure), cross‐over designs
cannot be used
d. B and C
e. All of the above - Answers :e. All of the above
Suppose a researcher is interested in assessing the adequacy of an instrument to
measure the theoretical conceptualization of "Quality of Pharmaceutical Care". The type
of validation procedure would most probably be:
a. Content
b. Concurrent
c. Construct
d. Face
e. Predictive - Answers :c. Construct
When the researcher simultaneously manipulates two independent variables, the
design is a:
a. Randomized control trial
b. Factorial design
c. Cross‐over design
d. Repeated measures design
e. Cohort study - Answers :b. Factorial design
A study is conducted retrospectively and collects data on patients who developed a
myocardial infarction (MI) and gathers data on another set of patients who haven't had a
MI. Differences in exposures to Drug A are compared between the groups, and an odds
ratio is calculated. This type of research design is known as:
a. Cross‐sectional
b. Case report
c. Cohort study
,d. Case/control study
e. None of the above - Answers :d. Case/control study
A study is internally valid if:
a. A repeated‐measures design was used.
b. A causal relationship is confirmed
c. An experimental design was used
d. All alternative explanations of the results can be ruled out
e. It can be generalized to the population - Answers :b. A causal relationship is
confirmed
d. All alternative explanations of the results can be ruled out
The use of inferential statistics permits the researcher to:
a. Generalize to a population based on information gathered from a sample
b. Interpret descriptive statistics
c. Describe information obtained from empirical observation
d. Reject the null hypothesis
e. Select a level of significance - Answers :a. Generalize to a population based on
information gathered from a sample
A study was conducted to evaluate an antibiotic in the treatment of possible bacteremia.
Five hundred children with fever but no focal infection were randomly assigned to the
antibiotic or to a placebo. All patients were reevaluated after 48 hours. The design used
in this study is best described as a
a. Randomized clinical trial
b. Placebo‐controlled trial
c. Controlled clinical trial
d. Cohort study - Answers :a. Randomized clinical trial
A study is conducted to compare the efficacy of two medications (Drug A and Drug
B) for the treatment of hypertension. One hundred patients are enrolled in the study
(50 receiving Drug A and 50 receiving Drug B). Which of the following terms BEST
describes patients receiving the study medications?
a. Population
b. Sample
c. Experimental group
d. Control group
e. None of the abov - Answers :b. Sample
Which of the following research designs would be the MOST optimal in terms of
controlling the study and producing valid results for a clinical trial comparing two
drugs?
, a. Prospective, randomized, double‐blind parallel study
b. Prospective experimental with historical control, open‐label, comparative study
c. Observational, double‐blind parallel study
d. Retrospective, parallel, longitudinal, open‐label study
e. A and C - Answers :a. Prospective, randomized, double‐blind parallel study
Patients may alter their behavior when they know they are being observed under
study conditions. Which of the following terms best describes this phenomenon?
a. Contamination bias
b. Selection bias
c. Volunteer bias
d. Attention bias (Hawthorne effect)
e. Admission rate bias (Berkson's paradox) - Answers :d. Attention bias (Hawthorne
effect)
Which of the following is TRUE with respect to the term "random chance?"
a. Outcomes of clinical trials may be affected by random chance
b. Statistical tests help to determine the effect of random chance on the study
outcomes
c. Random chance is also known as "systematic variation"
d. A and B
e. All of the above - Answers :d. A and B
Non‐probability sampling includes all of the following except:
a. Convenience sampling
b. Stratified sampling
c. Purposive sampling
d. Quota sampling
e. Snowball sampling - Answers :b. Stratified sampling
The proportion of people with disease, who have positive test results is referred to:
a. Specificity
b. Sensitivity
c. Responsiveness
d. None of the above - Answers :b. Sensitivity
Patients are recruited into a clinical trial. The main dependent variable is to
determine the average change in cholesterol level between 2 different medications
in a randomized, parallel, prospective, double‐blinded trial for the average person
living in America. An advertisement is placed on the wall of a local fitness center,
and patients from the fitness center respond to the advertisement. Based on this
information, which is the most likely bias to affect this study?
Subjects serve as their own controls in which of the following research design?
a. Factorial design
b. Parallel design
c. Cross‐over design
d. Randomized control trial
e. Case‐control study - Answers :c. Cross‐over design
The most effective method of controlling extraneous variables is by:
a. Analysis of covariance
b. Matching
c. Randomization
d. Use control group
e. None of the above - Answers :c. Randomization
A study is conducted to determine the efficacy of 2 drugs in preventing seasickness.
Measurements are taken to assess the following: no seasickness, mild seasickness,
or severe seasickness. Which of the following data types best describes these
measurements?
a. Nominal
b. Ordinal
c. Interval
d. Ratio
e. Integer - Answers :b. Ordinal
Which of the following best describes the function of the inclusion criteria for a study?
a. Assures patient safety
b. Describes the characteristics of the sample
c. Is important in evaluating the external validity of the study
d. B and C
e. None of the above - Answers :d. B and C
A study is conducted to determine the effect of Vitamin C tablets on mortality. After the
study is completed, the data indicate that patients taking Vitamin C tablets had a
decrease in mortality. However, the study design did not control for the effects of dietary
Vitamin C. Which of the following terms best describes the role of DIETARY Vitamin C
in this study?
a. Independent variable
b. Dependent variable
c. Confounding variable
d. Control variable
,e. None of the above - Answers :c. Confounding variable
In some non‐randomized studies, patients are assigned to certain treatment groups
based on some characteristic that they possess, which could affect the outcome of the
study. This type of bias is known as:
a. Volunteer bias
b. Contamination bias
c. Selection bias
d. Correlation bias
e. None of the above - Answers :c. Selection bias
One of the main limitations of a cross‐over design in drug studies in humans is:
a. The study is conducted during a specified time "window"
b. Requires a washout period to remove any residual effects from previous drug
treatments
c. If a drug induces a permanent effect (i.e. antibiotic cure), cross‐over designs
cannot be used
d. B and C
e. All of the above - Answers :e. All of the above
Suppose a researcher is interested in assessing the adequacy of an instrument to
measure the theoretical conceptualization of "Quality of Pharmaceutical Care". The type
of validation procedure would most probably be:
a. Content
b. Concurrent
c. Construct
d. Face
e. Predictive - Answers :c. Construct
When the researcher simultaneously manipulates two independent variables, the
design is a:
a. Randomized control trial
b. Factorial design
c. Cross‐over design
d. Repeated measures design
e. Cohort study - Answers :b. Factorial design
A study is conducted retrospectively and collects data on patients who developed a
myocardial infarction (MI) and gathers data on another set of patients who haven't had a
MI. Differences in exposures to Drug A are compared between the groups, and an odds
ratio is calculated. This type of research design is known as:
a. Cross‐sectional
b. Case report
c. Cohort study
,d. Case/control study
e. None of the above - Answers :d. Case/control study
A study is internally valid if:
a. A repeated‐measures design was used.
b. A causal relationship is confirmed
c. An experimental design was used
d. All alternative explanations of the results can be ruled out
e. It can be generalized to the population - Answers :b. A causal relationship is
confirmed
d. All alternative explanations of the results can be ruled out
The use of inferential statistics permits the researcher to:
a. Generalize to a population based on information gathered from a sample
b. Interpret descriptive statistics
c. Describe information obtained from empirical observation
d. Reject the null hypothesis
e. Select a level of significance - Answers :a. Generalize to a population based on
information gathered from a sample
A study was conducted to evaluate an antibiotic in the treatment of possible bacteremia.
Five hundred children with fever but no focal infection were randomly assigned to the
antibiotic or to a placebo. All patients were reevaluated after 48 hours. The design used
in this study is best described as a
a. Randomized clinical trial
b. Placebo‐controlled trial
c. Controlled clinical trial
d. Cohort study - Answers :a. Randomized clinical trial
A study is conducted to compare the efficacy of two medications (Drug A and Drug
B) for the treatment of hypertension. One hundred patients are enrolled in the study
(50 receiving Drug A and 50 receiving Drug B). Which of the following terms BEST
describes patients receiving the study medications?
a. Population
b. Sample
c. Experimental group
d. Control group
e. None of the abov - Answers :b. Sample
Which of the following research designs would be the MOST optimal in terms of
controlling the study and producing valid results for a clinical trial comparing two
drugs?
, a. Prospective, randomized, double‐blind parallel study
b. Prospective experimental with historical control, open‐label, comparative study
c. Observational, double‐blind parallel study
d. Retrospective, parallel, longitudinal, open‐label study
e. A and C - Answers :a. Prospective, randomized, double‐blind parallel study
Patients may alter their behavior when they know they are being observed under
study conditions. Which of the following terms best describes this phenomenon?
a. Contamination bias
b. Selection bias
c. Volunteer bias
d. Attention bias (Hawthorne effect)
e. Admission rate bias (Berkson's paradox) - Answers :d. Attention bias (Hawthorne
effect)
Which of the following is TRUE with respect to the term "random chance?"
a. Outcomes of clinical trials may be affected by random chance
b. Statistical tests help to determine the effect of random chance on the study
outcomes
c. Random chance is also known as "systematic variation"
d. A and B
e. All of the above - Answers :d. A and B
Non‐probability sampling includes all of the following except:
a. Convenience sampling
b. Stratified sampling
c. Purposive sampling
d. Quota sampling
e. Snowball sampling - Answers :b. Stratified sampling
The proportion of people with disease, who have positive test results is referred to:
a. Specificity
b. Sensitivity
c. Responsiveness
d. None of the above - Answers :b. Sensitivity
Patients are recruited into a clinical trial. The main dependent variable is to
determine the average change in cholesterol level between 2 different medications
in a randomized, parallel, prospective, double‐blinded trial for the average person
living in America. An advertisement is placed on the wall of a local fitness center,
and patients from the fitness center respond to the advertisement. Based on this
information, which is the most likely bias to affect this study?
