NRS 445 Exam 3 V1 | NRS 445 Nursing Research
and Evidence-Based Practice | Actual Q&A with
Rationale (NRS445 Exam 3) | Grand Canyon
University
1. A nurse researcher is planning a study and decides to use probability sampling to enhance
the representativeness of the sample. Which of the following techniques should the
researcher consider? Select all that apply.
A. Simple random sampling
B. Convenience sampling
C. Stratified random sampling
D. Quota sampling
E. Cluster sampling
F. Systematic sampling
Correct Answer: A, C, E, F
Explanation: Probability sampling involves random selection, which allows researchers to
estimate the probability that any element of the population will be included in the sample.
Simple random, stratified random, cluster, and systematic sampling are all forms of
probability sampling because they rely on randomization. Convenience and quota sampling
are non-probability methods, which are more prone to bias and lack generalizability.
,2. In a study examining the effect of a new wound care protocol on healing time, the nurse
identifies the healing time as which type of variable?
A. Independent variable
B. Extraneous variable
C. Dependent variable
D. Demographic variable
Correct Answer: C
Explanation: The dependent variable is the outcome or response that the researcher
wants to explain or predict. In this case, healing time is what is being measured to see if the
intervention had an effect. The wound care protocol itself would be the independent
variable.
3. When evaluating the reliability of a new tool designed to measure patient anxiety, a
researcher calculates a Cronbach’s alpha coefficient of 0.85. How should this result be
interpreted?
A. The tool has acceptable internal consistency for a clinical instrument.
B. The tool has poor internal consistency and should be revised.
C. The tool is highly valid but not reliable.
D. The tool measures exactly what it is intended to measure.
Correct Answer: A
, Explanation: Cronbach’s alpha is a measure of internal consistency reliability, ranging
from 0 to 1. A coefficient of 0.85 is generally considered good to excellent for most research
instruments, indicating that the items within the tool are highly correlated. This score
suggests the instrument is consistently measuring the construct of anxiety.
4. A researcher is reviewing a study where the p-value is reported as 0.02. If the alpha level
was set at 0.05, what conclusion should the researcher draw regarding the null hypothesis?
A. Fail to reject the null hypothesis.
B. Reject the null hypothesis.
C. The results are clinically significant but not statistically significant.
D. The study has a high risk of a Type II error.
Correct Answer: B
Explanation: The p-value represents the probability that the observed result occurred by
chance. Since 0.02 is less than the pre-specified alpha level of 0.05, the results are
considered statistically significant. Therefore, the researcher should reject the null
hypothesis in favor of the alternative hypothesis.
5. Qualitative research is distinct from quantitative research in its approach to data and
reality. Which features are characteristic of qualitative research designs? Select all that apply.
A. Subjective focus
B. Deductive reasoning
C. Holistic perspective
and Evidence-Based Practice | Actual Q&A with
Rationale (NRS445 Exam 3) | Grand Canyon
University
1. A nurse researcher is planning a study and decides to use probability sampling to enhance
the representativeness of the sample. Which of the following techniques should the
researcher consider? Select all that apply.
A. Simple random sampling
B. Convenience sampling
C. Stratified random sampling
D. Quota sampling
E. Cluster sampling
F. Systematic sampling
Correct Answer: A, C, E, F
Explanation: Probability sampling involves random selection, which allows researchers to
estimate the probability that any element of the population will be included in the sample.
Simple random, stratified random, cluster, and systematic sampling are all forms of
probability sampling because they rely on randomization. Convenience and quota sampling
are non-probability methods, which are more prone to bias and lack generalizability.
,2. In a study examining the effect of a new wound care protocol on healing time, the nurse
identifies the healing time as which type of variable?
A. Independent variable
B. Extraneous variable
C. Dependent variable
D. Demographic variable
Correct Answer: C
Explanation: The dependent variable is the outcome or response that the researcher
wants to explain or predict. In this case, healing time is what is being measured to see if the
intervention had an effect. The wound care protocol itself would be the independent
variable.
3. When evaluating the reliability of a new tool designed to measure patient anxiety, a
researcher calculates a Cronbach’s alpha coefficient of 0.85. How should this result be
interpreted?
A. The tool has acceptable internal consistency for a clinical instrument.
B. The tool has poor internal consistency and should be revised.
C. The tool is highly valid but not reliable.
D. The tool measures exactly what it is intended to measure.
Correct Answer: A
, Explanation: Cronbach’s alpha is a measure of internal consistency reliability, ranging
from 0 to 1. A coefficient of 0.85 is generally considered good to excellent for most research
instruments, indicating that the items within the tool are highly correlated. This score
suggests the instrument is consistently measuring the construct of anxiety.
4. A researcher is reviewing a study where the p-value is reported as 0.02. If the alpha level
was set at 0.05, what conclusion should the researcher draw regarding the null hypothesis?
A. Fail to reject the null hypothesis.
B. Reject the null hypothesis.
C. The results are clinically significant but not statistically significant.
D. The study has a high risk of a Type II error.
Correct Answer: B
Explanation: The p-value represents the probability that the observed result occurred by
chance. Since 0.02 is less than the pre-specified alpha level of 0.05, the results are
considered statistically significant. Therefore, the researcher should reject the null
hypothesis in favor of the alternative hypothesis.
5. Qualitative research is distinct from quantitative research in its approach to data and
reality. Which features are characteristic of qualitative research designs? Select all that apply.
A. Subjective focus
B. Deductive reasoning
C. Holistic perspective
