Certified Midwife Exam Prep Research & Evidence-Based Practice 3 — Questions and Answers
Question 1: A midwife is evaluating a screening test for preeclampsia. The test has high sensitivity but low specificity. Which statement is MOST accurate?
- The test rarely misses true cases but produces many false positives (Correct answer)
- The test rarely produces false positives but misses many cases
- Both sensitivity and specificity must exceed 90% for clinical use
- High sensitivity means the test is better at ruling in disease
Correct answer: The test rarely misses true cases but produces many false positives
High sensitivity means few false negatives (misses), while low specificity means many false positives, making the test good for ruling out disease.
Question 2: Which of the following is an example of selection bias in midwifery research?
- Participants in a labor pain study drop out because the intervention is ineffective
- Only low-risk women volunteer for a home birth study, skewing outcomes (Correct answer)
- A researcher inadvertently records data in favor of the experimental group
- Survey questions are worded to lead respondents toward certain answers
Correct answer: Only low-risk women volunteer for a home birth study, skewing outcomes
When study participants are not representative of the target population—such as only low-risk women volunteering—selection bias occurs, limiting generalizability.
Question 3: A meta-analysis reports high heterogeneity (I² = 78%). What is the MOST appropriate conclusion?
- The pooled result is highly reliable and should guide practice directly
- Results vary substantially across studies, so the pooled estimate should be interpreted cautiously (Correct answer)
- The meta-analysis should be discarded as unreliable
- An I² above 50% always indicates methodological flaws in the included studies
Correct answer: Results vary substantially across studies, so the pooled estimate should be interpreted cautiously
I² of 78% indicates substantial heterogeneity, meaning study results varied considerably; the pooled estimate should be interpreted with caution and heterogeneity sources explored.
Question 4: In qualitative research, which sampling strategy is used to deliberately seek participants who can provide the richest information on the phenomenon of interest?
- Simple random sampling
- Systematic sampling
- Purposive sampling (Correct answer)
- Convenience sampling
Correct answer: Purposive sampling
Purposive (purposeful) sampling intentionally selects participants based on their ability to provide meaningful, information-rich data relevant to the research question.
Question 5: Which component of a PICO question represents the comparison against which an intervention is measured?
- Population
- Intervention
- Comparison (Correct answer)
- Outcome
Correct answer: Comparison
The 'C' in PICO stands for Comparison, which may be standard care, placebo, or an alternative intervention used as the reference group.
Question 6: A midwifery student reads a qualitative study using grounded theory. What is the PRIMARY goal of grounded theory research?
- To test a pre-existing hypothesis with statistical methods
- To generate a theory grounded in data collected from participants (Correct answer)
- To describe the lived experience of a phenomenon
- To identify correlations between variables in a large sample
Correct answer: To generate a theory grounded in data collected from participants
Grounded theory is an inductive qualitative method whose goal is to develop a theory that emerges from systematically gathered and analyzed data.
Question 7: When a midwife applies EBP, which step follows the formulation of a clinical question?
- Implement the best available evidence immediately
- Search for the best available evidence (Correct answer)
- Critically appraise the current clinical guideline
- Evaluate the impact of the practice change
Correct answer: Search for the best available evidence
The five steps of EBP are: Ask, Acquire (search for evidence), Appraise, Apply, and Assess; searching for evidence follows question formulation.
Certified Midwife Exam Prep Research & Evidence-Based Practice 3
A midwife is evaluating a screening test for preeclampsia.
The test has high sensitivity but low specificity.
Which statement is MOST accurate?