Cardiac Vascular Nursing Exam Research & Evidence-Based Practice 3 — Questions and Answers
Question 1: A cardiovascular nurse researcher is designing a study on nurse-led hypertension clinics. Which study design BEST establishes causality between the intervention and blood pressure outcomes?
- Retrospective chart review
- Cross-sectional survey
- Prospective randomized controlled trial (Correct answer)
- Case-control study
Correct answer: Prospective randomized controlled trial
A prospective RCT with randomization and a control group is the gold-standard design for establishing causality between an intervention and outcomes.
Question 2: In evidence-based practice, the PICO framework is used to formulate clinical questions. In a cardiac nursing PICO question, what does the 'C' represent?
- Clinical setting
- Comparison intervention or control (Correct answer)
- Confidence interval
- Contraindication
Correct answer: Comparison intervention or control
In PICO, 'C' stands for Comparison — the alternative intervention, standard care, or placebo to which the intervention is being compared.
Question 3: A meta-analysis on beta-blocker use post-MI reports a 95% confidence interval for mortality risk reduction of 0.75–0.95. Which conclusion is MOST accurate?
- There is a 5% chance the true effect falls outside this range
- The treatment increases mortality in 5% of patients
- The results are statistically significant since the interval excludes 1.0 (Correct answer)
- The study power is insufficient to detect a real effect
Correct answer: The results are statistically significant since the interval excludes 1.0
A 95% CI that does not cross 1.0 for a relative risk or odds ratio indicates a statistically significant result, here showing reduced mortality.
Question 4: Which type of research bias occurs when cardiac surgery patients with complications are less likely to complete follow-up questionnaires, skewing outcomes data?
- Recall bias
- Attrition bias (Correct answer)
- Hawthorne effect
- Confounding bias
Correct answer: Attrition bias
Attrition bias occurs when participants who drop out differ systematically from those who complete the study, skewing results toward more favorable outcomes.
Question 5: A cardiac unit implements a quality improvement (QI) project on door-to-balloon time. How does QI differ from research in terms of IRB requirements?
- QI projects always require full IRB review unlike research
- QI projects aimed at improving local practice typically do not require IRB approval (Correct answer)
- Both QI and research require identical IRB oversight
- Only multi-site QI projects need IRB review
Correct answer: QI projects aimed at improving local practice typically do not require IRB approval
QI projects designed to improve local institutional practice are generally exempt from IRB review, while research intended to generate generalizable knowledge requires IRB approval.
Question 6: When searching for evidence on cardiac rehabilitation, a nurse finds a funnel plot that is asymmetrical in a meta-analysis. This MOST likely indicates:
- High statistical heterogeneity among studies
- Publication bias with missing small negative studies (Correct answer)
- Inadequate blinding in included RCTs
- Overly broad inclusion criteria
Correct answer: Publication bias with missing small negative studies
An asymmetrical funnel plot in a meta-analysis suggests publication bias, commonly because small studies with negative results are less likely to be published.
Question 7: A nurse critically appraises a cohort study on long-term anticoagulation and major bleeding. The study reports a hazard ratio (HR) of 1.8 (95% CI 1.2–2.7). What is the CORRECT interpretation?
- Patients on anticoagulation have an 80% higher rate of major bleeding events (Correct answer)
- Anticoagulation reduces bleeding events by 80%
- The 80% increased risk is not statistically significant
- The hazard ratio indicates a causal relationship
Correct answer: Patients on anticoagulation have an 80% higher rate of major bleeding events
An HR of 1.8 means the rate of major bleeding is 80% higher in the anticoagulation group; since the CI excludes 1.0, this is statistically significant.
Cardiac Vascular Nursing Exam Research & Evidence-Based Practice 3
A cardiovascular nurse researcher is designing a study on nurse-led hypertension clinics.
Which study design BEST establishes causality between the intervention and blood pressure outcomes?