Slideshow Videos Research & Evidence-Based Practice 4 — Questions and Answers
Question 1: In evidence-based practice, which step comes AFTER formulating a clinical question?
- Implement the intervention immediately
- Search for the best available evidence (Correct answer)
- Evaluate patient outcomes
- Obtain informed consent
Correct answer: Search for the best available evidence
The EBP process follows: Ask → Acquire evidence → Appraise → Apply → Evaluate; searching for evidence is the second step.
Question 2: What does the term 'statistical power' refer to in research?
- The ability of a study to detect a true effect when one exists (Correct answer)
- The strength of a statistical association
- The probability of making a Type I error
- The size of the effect observed
Correct answer: The ability of a study to detect a true effect when one exists
Statistical power is the probability that a study will detect a true difference or effect when one actually exists (1 - β).
Question 3: Which of the following BEST describes a cross-sectional study?
- Participants are followed forward in time from exposure to outcome
- Data on exposure and outcome are collected at the same point in time (Correct answer)
- Cases with the outcome are compared to controls without it
- Participants are randomly assigned to intervention groups
Correct answer: Data on exposure and outcome are collected at the same point in time
A cross-sectional study measures both exposure and outcome simultaneously, providing a snapshot of a population at one time point.
Question 4: A p-value of 0.03 means:
- There is a 3% chance the null hypothesis is true
- There is a 3% probability of observing results this extreme if the null hypothesis were true (Correct answer)
- The clinical effect size is large
- The result will replicate 97% of the time
Correct answer: There is a 3% probability of observing results this extreme if the null hypothesis were true
A p-value represents the probability of obtaining results at least as extreme as observed, assuming the null hypothesis is true.
Question 5: What is a limitation of using expert opinion as evidence in clinical practice?
- It is too difficult to obtain
- It is subject to individual bias and may not reflect current data (Correct answer)
- It requires IRB approval
- It cannot be used in systematic reviews
Correct answer: It is subject to individual bias and may not reflect current data
Expert opinion sits at the lowest level of evidence because it is vulnerable to personal bias and may not be based on rigorous research.
Question 6: When critically appraising a study, which question addresses INTERNAL validity?
- Can the results be applied to my patients?
- Was the study conducted in a similar setting to mine?
- Were participants randomly assigned and groups comparable at baseline? (Correct answer)
- Was the sample size large enough to generalize?
Correct answer: Were participants randomly assigned and groups comparable at baseline?
Internal validity concerns whether the study's results accurately reflect the true relationship within the study itself, including proper randomization and baseline comparability.
Question 7: A researcher uses a Likert scale to measure patient satisfaction. This instrument produces which type of data?
- Nominal
- Ratio
- Ordinal (Correct answer)
- Interval
Correct answer: Ordinal
Likert scales produce ordinal data because responses have a meaningful order but intervals between categories are not necessarily equal.
Slideshow Videos Research & Evidence-Based Practice 4
In evidence-based practice, which step comes AFTER formulating a clinical question?