Cardiac Vascular Nursing Exam Research & Evidence-Based Practice 2 — Questions and Answers
Question 1: When critically appraising a randomized controlled trial (RCT) on anticoagulation therapy, which element BEST indicates internal validity?
- Large sample size with diverse demographics
- Allocation concealment preventing selection bias (Correct answer)
- Use of open-label drug administration
- Long follow-up duration beyond 12 months
Correct answer: Allocation concealment preventing selection bias
Allocation concealment prevents researchers from knowing group assignments before randomization, protecting against selection bias and ensuring internal validity.
Question 2: A cardiac nurse wants to implement a new evidence-based protocol for post-PCI care. Which framework is MOST appropriate for guiding this practice change?
- Donabedian model
- Iowa Model of Evidence-Based Practice (Correct answer)
- Lewin's Force Field Analysis
- Benner's Novice-to-Expert Model
Correct answer: Iowa Model of Evidence-Based Practice
The Iowa Model provides a stepwide framework specifically designed to guide evidence-based practice changes in clinical settings, including trigger identification, team formation, and pilot testing.
Question 3: In a study on cardiac rehabilitation outcomes, the p-value is reported as 0.03. What does this indicate?
- There is a 3% chance the intervention caused the outcome
- There is a 3% probability the results occurred by chance alone (Correct answer)
- The effect size is clinically meaningful
- The study has 97% statistical power
Correct answer: There is a 3% probability the results occurred by chance alone
A p-value of 0.03 means there is a 3% probability of obtaining the observed results (or more extreme) if the null hypothesis were true.
Question 4: A systematic review on thrombolytic therapy for acute MI reports a Number Needed to Treat (NNT) of 25. How should a cardiovascular nurse interpret this?
- 25 patients must be treated for one patient to experience benefit (Correct answer)
- The treatment benefits 25% of patients treated
- 25 adverse events occur per 100 patients treated
- The treatment reduces mortality by 25%
Correct answer: 25 patients must be treated for one patient to experience benefit
NNT of 25 means 25 patients must receive the treatment for one additional patient to achieve the desired outcome compared to control.
Question 5: Which level of evidence is considered HIGHEST in the evidence hierarchy for cardiac nursing practice decisions?
- Expert opinion from cardiovascular specialists
- Well-designed cohort studies
- Systematic review with meta-analysis of RCTs (Correct answer)
- Single large randomized controlled trial
Correct answer: Systematic review with meta-analysis of RCTs
Systematic reviews with meta-analysis of multiple RCTs represent the highest level of evidence by synthesizing data across studies, reducing random error and bias.
Question 6: A nurse is evaluating a study reporting a relative risk reduction (RRR) of 50% for statin therapy. The control group event rate is 4%. What is the absolute risk reduction (ARR)?
- 50%
- 25%
- 2% (Correct answer)
- 0.5%
Correct answer: 2%
ARR = control event rate × RRR = 4% × 50% = 2%, meaning the absolute difference in event rates between groups is 2%.
Question 7: When implementing evidence-based anticoagulation guidelines, a nurse notices a conflict between two high-quality systematic reviews. What is the BEST next step?
- Follow the older, more established guideline
- Choose the review with the larger sample size
- Consult an interdisciplinary team and examine guideline methodology differences (Correct answer)
- Default to physician preference until evidence is settled
Correct answer: Consult an interdisciplinary team and examine guideline methodology differences
When evidence conflicts, convening an interdisciplinary team and examining methodological differences between reviews allows for the most informed, patient-centered decision.
Cardiac Vascular Nursing Exam Research & Evidence-Based Practice 2
When critically appraising a randomized controlled trial (RCT) on anticoagulation therapy, which element BEST indicates internal validity?