Deck 7: Experimental Research

Question 1

Which type of quantitative research design looks for cause and effect between an intervention variable and an outcome variable?

A) Correlational design
B) Case control design
C) Experimental design
D) Retrospective design

Answer 1

C

Question 2

Which of the following is not a key feature of experimental studies?

A) Consistent delivery of well-defined intervention variables
B) Random assignment of participants to intervention and comparison groups
C) Flexibility in data collection
D) Control of extraneous influences and bias

Answer 2

C

Question 3

Which of the following results from a sample size that is too small?

A) Low power to detect a difference in the outcomes of the two groups
B) Lack of control over extraneous variables
C) Limits to random sampling
D) A weak intervention

Answer 3

A

Question 4

Inconsistent delivery of either or both of the treatments has what effect on the results of the study?

A) None, if the researcher corrects the inconsistency before the end of the study.
B) It could cause the study participants to be dissatisfied with their involvement in the study.
C) It could affect the inter-rater reliability of the outcome variable.
D) It could result in erroneous study conclusions.

Question 5

In a two-group intervention study, what is the meaning of a t-test with p value of 0.03 result?

A) There is a high probability that in the population the two groups are truly different on the outcome.
B) There is a low probability that in the population the two groups are truly different.
C) The two groups had similar outcomes.
D) The probability of the outcome occurring is low.

Question 6

What statement can be accurately said about missing data?

A) The amount and pattern of missing data should be analyzed carefully.
B) It is a major concern at any level of occurrence.
C) When missing data occurs, the case should be dropped from the study.
D) It is a concern when the level is above 5%.

Question 7

In experimental research, which of the following is not a type of comparison intervention?

A) A random intervention
B) A placebo intervention
C) A usual care intervention
D) No intervention at all

Question 8

What is the main goal of a two-group experimental study?

A) To determine if the sample is representative of the population
B) To determine if one intervention is more effective than the other
C) To determine if either intervention is biased
D) To determine if both interventions can be safely implemented in real settings

Question 9

Researchers can run t-tests on which type of variables?

A) A group variable and a continuous variable
B) Two criterion variables
C) Two dichotomous variables
D) An active variable and a correlational variable

Question 10

Why is a study categorized as quasi-experimental (as opposed to being called an experimental study)?

A) Because the researcher does not have a PhD
B) Because the intervention was only partially tested
C) Because the intervention and/or setting was not tightly controlled
D) Because it was not possible to recruit participants from the population of interest

Question 11

Calculate the Numbers Needed to Treat (NNT) for the effect of exercise on sleep using the following fictitious data: In a study of exercise in the elderly, 20% of persons in the exercise group reported better sleep, whereas 4% did so in the comparison group.

A) NNT = 16
B) NNT = 8
C) NNT = 5
D) NNT = 7

Question 12

What does Numbers Needed to Treat (NNT) indicate?

A) The number of persons per 100 who would have to be treated with an intervention to achieve a particular outcome
B) The number of persons per 100 in the population who would benefit from the intervention
C) The number of persons who would have to be treated with an intervention rather than the comparison intervention to achieve one more person attaining the particular outcome
D) The numbers of persons in the intervention group who achieved the particular outcome

Question 13

In a study of the effectiveness of two pain management methods, what is the meaning of the conclusion that one method produced a clinically significant lower pain level than the other method?

A) The difference in outcome achieved by the more effective method is large enough to make an important difference in patient comfort.
B) Pain management is an important intervention.
C) The study was well-conducted.
D) The difference in outcomes achieved by the two groups proves the underlying physiology being tested.

Question 14

All of the following are key features of a well-designed experimental study, except:

A) data saturation.
B) random assignment to groups.
C) low level of missing data.
D) control of extraneous variables.

Question 15

A common reason for low statistical power in a study is:

A) small sample size.
B) lack of an independent variable.
C) large sample size.
D) lack of a correlational variable.

Question 16

The problem with low statistical power is:

A) the p value cut point is set too high.
B) a significant result is too easy to achieve.
C) the statistical analysis is weakened by small sample size.
D) a weak sampling method was used.

Question 17

The process of blinding ensures that:

A) bias is minimized.
B) privacy is maximized.
C) confidentiality is protected.
D) anonymity is protected.

Question 18

In the exemplar study about pain relief during intravenous cannula insertion in children (Canbulat, 2015), why did the researchers obtain a pre-procedure, self-report anxiety score?

A) So they could compare it to the score after the procedure
B) To be sure both treatment groups were similar before the procedure
C) To reduce the child's anxiety level
D) To give the child practice in self-reporting anxiety after the procedure

Question 19

In the exemplar study about pain relief during intravenous cannula insertion in children (Canbulat, 2015), what confounding variable could have been at work?

A) The Buzzy device could have acted as attention and thereby influenced anxiety and pain perceptions.
B) The IV cannula insertion may have been more difficult in some children.
C) The data collector could have increased the children's anxiety levels.
D) The parents' presence could have affected the children's scoring of pain and anxiety.

Question 20

What is the relationship between clinical significance and statistical significance?

A) If one is significant, the other is significant.
B) Both can be significant, both can be nonsignificant, or one can be significant and the other nonsignificant.
C) Statistical significance determines clinical significance.
D) Clinical significance determines the reliability of statistical significance.

Question 21

All of the following statements are true about the use of a t-test, except:

A) it includes a level of significance.
B) it is used to analyze interval level data.
C) it analyzes the difference between two means.
D) it is used to analyze dichotomous outcomes.

Question 22

Which of the following is not an important function of study protocols?

A) They promote consistent delivery of the interventions.
B) They assure that persons in both groups are treated similarly except for the intervention they receive.
C) They assure that patients give honest answers.
D) They promote the control of bias.

Question 23

Which statement is true of experimental design?

A) It is always the best design and should be used whenever possible.
B) It provides control of all extraneous variables.
C) It is the best design for evaluating the effectiveness of clinical interventions and treatments.
D) It works well for small sample sizes.

Question 24

What concern exists to a greater extent in quasi-experimental studies than in experimental studies?

A) The Hawthorne effect
B) Too small a sample size
C) Low statistical power
D) The influence of extraneous variables

Question 25

Ideally, in experimental research, how is sample size determined?

A) Theoretically
B) Randomly
C) Using profiling based on prior research
D) Through a power analysis

Question 26

Training the staff or research assistants who will deliver the interventions assures which one of the following goals of an experimental study?

A) A high level of patient participation
B) Accurate and unbiased measurement of the study outcomes
C) Data collectors who know which intervention the patient received
D) Consistent delivery of the interventions