NRS 445 Exam 2 V2 | NRS 445 Nursing Research
and Evidence-Based Practice | Actual Q&A with
Rationale (NRS445 Exam 2) | Grand Canyon
University
1. A nurse researcher is planning a quantitative study and wishes to utilize probability
sampling to enhance the generalizability of the findings. Which of the following methods are
categorized as probability sampling? (Select all that apply)
A. Simple random sampling
B. Convenience sampling
C. Stratified random sampling
D. Quota sampling
E. Cluster sampling
F. Snowball sampling
Correct Answer: A, C, E
Explanation: Probability sampling involves random selection, ensuring every member of
the population has a known, non-zero chance of being selected. Simple random, stratified
random, and cluster sampling are all rigorous methods that use randomization to reduce
selection bias. Conversely, convenience, quota, and snowball sampling are non-probability
methods that rely on non-random criteria, which limits the external validity of the study.
,2. When evaluating a research study, the nurse notes that the p-value is 0.02. If the alpha
level was set at 0.05, how should the researcher interpret this finding?
A. Fail to reject the null hypothesis
B. The result is not statistically significant
C. Reject the null hypothesis
D. The research hypothesis is proven false
Correct Answer: C
Explanation: The p-value represents the probability that the observed results occurred by
chance; a p-value of 0.02 is less than the alpha of 0.05. This indicates that the results are
statistically significant, leading the researcher to reject the null hypothesis. Rejecting the
null hypothesis suggests that there is a relationship or difference between variables that is
likely not due to random chance.
3. In the evidence-based practice hierarchy, which of the following is considered the highest
level of evidence (Level I)?
A. Single randomized controlled trial (RCT)
B. Case-control studies
C. Cohort studies
D. Systematic review or meta-analysis of RCTs
Correct Answer: D
,Explanation: The hierarchy of evidence places systematic reviews and meta-analyses of all
relevant randomized controlled trials at the top (Level I) because they synthesize data from
multiple high-quality studies. A single RCT is typically considered Level II evidence. This
structure helps clinicians identify the most robust evidence to guide clinical decision-
making and improve patient outcomes.
4. A researcher is studying the effect of a new wound dressing on the healing time of pressure
ulcers. In this study, what is the independent variable?
A. The pressure ulcer
B. The new wound dressing
C. The healing time
D. The age of the patient
Correct Answer: B
Explanation: The independent variable is the intervention or condition that is
manipulated by the researcher to observe its effect on an outcome. In this scenario, the new
wound dressing is being tested to see if it causes a change. The healing time is the
dependent variable, as it is the outcome being measured by the researcher.
5. Which type of research design is most appropriate for exploring the lived experiences of
individuals undergoing chemotherapy?
A. Experimental design
B. Quasi-experimental design
, C. Phenomenology
D. Correlational design
Correct Answer: C
Explanation: Phenomenology is a qualitative research approach focused on describing the
common meaning of several individuals’ lived experiences of a concept or phenomenon.
Since the study seeks to understand the personal ‘lived experience’ of chemotherapy,
qualitative methods are required. Experimental and correlational designs are quantitative
and would focus on numerical data or cause-and-effect rather than subjective meaning.
6. A nurse is reviewing a study where the Cronbach’s alpha for an assessment tool was
reported as 0.85. How should the nurse interpret this value?
A. The tool has poor internal consistency.
B. The tool has a high degree of measurement error.
C. The tool lacks content validity.
D. The tool has excellent internal consistency.
Correct Answer: D
Explanation: Cronbach’s alpha is a measure of internal consistency reliability, indicating
how well items on a scale measure the same construct. A value of 0.85 is generally
considered high, suggesting that the instrument is reliable for research purposes.
Generally, a value above 0.70 is acceptable, while values above 0.80 are considered strong
for clinical tools.
and Evidence-Based Practice | Actual Q&A with
Rationale (NRS445 Exam 2) | Grand Canyon
University
1. A nurse researcher is planning a quantitative study and wishes to utilize probability
sampling to enhance the generalizability of the findings. Which of the following methods are
categorized as probability sampling? (Select all that apply)
A. Simple random sampling
B. Convenience sampling
C. Stratified random sampling
D. Quota sampling
E. Cluster sampling
F. Snowball sampling
Correct Answer: A, C, E
Explanation: Probability sampling involves random selection, ensuring every member of
the population has a known, non-zero chance of being selected. Simple random, stratified
random, and cluster sampling are all rigorous methods that use randomization to reduce
selection bias. Conversely, convenience, quota, and snowball sampling are non-probability
methods that rely on non-random criteria, which limits the external validity of the study.
,2. When evaluating a research study, the nurse notes that the p-value is 0.02. If the alpha
level was set at 0.05, how should the researcher interpret this finding?
A. Fail to reject the null hypothesis
B. The result is not statistically significant
C. Reject the null hypothesis
D. The research hypothesis is proven false
Correct Answer: C
Explanation: The p-value represents the probability that the observed results occurred by
chance; a p-value of 0.02 is less than the alpha of 0.05. This indicates that the results are
statistically significant, leading the researcher to reject the null hypothesis. Rejecting the
null hypothesis suggests that there is a relationship or difference between variables that is
likely not due to random chance.
3. In the evidence-based practice hierarchy, which of the following is considered the highest
level of evidence (Level I)?
A. Single randomized controlled trial (RCT)
B. Case-control studies
C. Cohort studies
D. Systematic review or meta-analysis of RCTs
Correct Answer: D
,Explanation: The hierarchy of evidence places systematic reviews and meta-analyses of all
relevant randomized controlled trials at the top (Level I) because they synthesize data from
multiple high-quality studies. A single RCT is typically considered Level II evidence. This
structure helps clinicians identify the most robust evidence to guide clinical decision-
making and improve patient outcomes.
4. A researcher is studying the effect of a new wound dressing on the healing time of pressure
ulcers. In this study, what is the independent variable?
A. The pressure ulcer
B. The new wound dressing
C. The healing time
D. The age of the patient
Correct Answer: B
Explanation: The independent variable is the intervention or condition that is
manipulated by the researcher to observe its effect on an outcome. In this scenario, the new
wound dressing is being tested to see if it causes a change. The healing time is the
dependent variable, as it is the outcome being measured by the researcher.
5. Which type of research design is most appropriate for exploring the lived experiences of
individuals undergoing chemotherapy?
A. Experimental design
B. Quasi-experimental design
, C. Phenomenology
D. Correlational design
Correct Answer: C
Explanation: Phenomenology is a qualitative research approach focused on describing the
common meaning of several individuals’ lived experiences of a concept or phenomenon.
Since the study seeks to understand the personal ‘lived experience’ of chemotherapy,
qualitative methods are required. Experimental and correlational designs are quantitative
and would focus on numerical data or cause-and-effect rather than subjective meaning.
6. A nurse is reviewing a study where the Cronbach’s alpha for an assessment tool was
reported as 0.85. How should the nurse interpret this value?
A. The tool has poor internal consistency.
B. The tool has a high degree of measurement error.
C. The tool lacks content validity.
D. The tool has excellent internal consistency.
Correct Answer: D
Explanation: Cronbach’s alpha is a measure of internal consistency reliability, indicating
how well items on a scale measure the same construct. A value of 0.85 is generally
considered high, suggesting that the instrument is reliable for research purposes.
Generally, a value above 0.70 is acceptable, while values above 0.80 are considered strong
for clinical tools.
