CMD Research Methods & Evidence-Based Practice 2 — Questions and Answers
Question 1: A Medical Director reviews a study where patients were randomly assigned to treatment or control groups, and neither patients nor researchers knew who received the treatment. What study design is this?
- Open-label randomized trial
- Double-blind randomized controlled trial (Correct answer)
- Prospective cohort study
- Crossover observational study
Correct answer: Double-blind randomized controlled trial
A double-blind RCT assigns participants randomly while masking both participants and investigators to treatment allocation, minimizing performance and detection bias.
Question 2: Which statistical measure best describes the strength of association between a risk factor and an outcome in a case-control study?
- Relative risk
- Odds ratio (Correct answer)
- Number needed to treat
- Attributable risk
Correct answer: Odds ratio
Case-control studies calculate odds ratios because incidence rates cannot be directly determined from this retrospective design.
Question 3: A CMD evaluates a quality improvement initiative. The PDSA cycle stands for:
- Plan, Do, Study, Act (Correct answer)
- Prepare, Deploy, Sustain, Assess
- Plan, Develop, Survey, Adjust
- Prioritize, Design, Standardize, Audit
Correct answer: Plan, Do, Study, Act
The Plan-Do-Study-Act cycle is the foundational iterative model for quality improvement in healthcare settings.
Question 4: In a clinical study, the p-value is 0.03 with a significance threshold of 0.05. Which conclusion is most appropriate?
- The result is clinically meaningful
- The null hypothesis is rejected (Correct answer)
- The effect size is large
- The study has adequate power
Correct answer: The null hypothesis is rejected
A p-value below the predetermined alpha (0.05) indicates sufficient evidence to reject the null hypothesis, though this does not confirm clinical significance.
Question 5: A Medical Director wants to understand why nursing staff resist a new protocol. Which research approach is most appropriate?
- Randomized controlled trial
- Retrospective chart review
- Qualitative focus groups (Correct answer)
- Meta-analysis of existing literature
Correct answer: Qualitative focus groups
Qualitative methods such as focus groups elicit in-depth perspectives on attitudes, beliefs, and experiences underlying behavioral resistance.
Question 6: Sensitivity of a screening test refers to its ability to:
- Correctly identify true negatives
- Correctly identify true positives (Correct answer)
- Minimize false positive results
- Predict disease severity
Correct answer: Correctly identify true positives
Sensitivity measures the proportion of people with the disease who test positive (true positive rate), reflecting the test's ability to detect disease.
Question 7: Which level of the evidence hierarchy carries the highest quality for evaluating treatment effectiveness?
- Expert opinion
- Case series
- Systematic review with meta-analysis (Correct answer)
- Single RCT
Correct answer: Systematic review with meta-analysis
Systematic reviews with meta-analyses synthesize data from multiple high-quality RCTs and sit at the top of most evidence hierarchies for treatment questions.
CMD Research Methods & Evidence-Based Practice 2
A Medical Director reviews a study where patients were randomly assigned to treatment or control groups, and neither patients nor researchers knew who received the treatment.
What study design is this?