ATC Evidence-Based Practice 5 — Questions and Answers
Question 1: A case-control study recruits individuals WITH a condition (cases) and WITHOUT a condition (controls). This design is BEST for studying:
- Treatment effectiveness of a new intervention
- Rare diseases or conditions with long latency periods (Correct answer)
- Prevalence of a condition in a defined population
- Normal reference ranges for clinical measurements
Correct answer: Rare diseases or conditions with long latency periods
Case-control studies are efficient for rare conditions because they start with known cases and compare retrospective exposure histories with matched controls.
Question 2: Publication bias in research refers to:
- Journals publishing only studies with large sample sizes
- The tendency for positive results to be published more often than null results (Correct answer)
- Researchers publishing the same data in multiple journals
- Bias introduced by the publication date of a study
Correct answer: The tendency for positive results to be published more often than null results
Publication bias skews the available evidence base toward positive findings, as studies with statistically significant results are more likely to be published.
Question 3: An athletic trainer uses a clinical prediction rule (CPR) that has been validated in a population different from their patient. The MOST appropriate action is to:
- Apply the CPR without modification since it is validated
- Disregard the CPR entirely and use clinical judgment alone
- Apply the CPR cautiously while considering differences between populations (Correct answer)
- Only use CPRs validated in the same setting
Correct answer: Apply the CPR cautiously while considering differences between populations
CPRs developed in different populations may have reduced accuracy; clinicians should note population differences and apply CPRs with appropriate caution.
Question 4: Which statistical measure is used to quantify the agreement between two categorical raters beyond chance?
- Pearson's r
- Intraclass correlation coefficient
- Cohen's kappa (Correct answer)
- Spearman's rho
Correct answer: Cohen's kappa
Cohen's kappa measures inter-rater agreement for categorical variables, accounting for the level of agreement expected by chance alone.
Question 5: In the context of EBP, patient values and preferences refer to:
- The patient's laboratory values and physical measurements
- The patient's unique concerns, expectations, and goals regarding their care (Correct answer)
- Standardized patient satisfaction survey results
- The clinician's preference for a specific patient population
Correct answer: The patient's unique concerns, expectations, and goals regarding their care
Patient values and preferences encompass individual patient goals, concerns, cultural beliefs, and expectations that must be integrated into clinical decision-making.
Question 6: A study reports a likelihood ratio positive (LR+) of 8.5 for a special orthopedic test. This indicates:
- The test has 85% sensitivity
- A positive test result substantially increases the post-test probability of the condition (Correct answer)
- The test should not be used clinically
- The test has high specificity but low sensitivity
Correct answer: A positive test result substantially increases the post-test probability of the condition
An LR+ of 8.5 is considered large and substantially shifts the probability of diagnosis toward the condition when the test is positive.
Question 7: Which research design is MOST susceptible to recall bias?
- Prospective randomized controlled trial
- Retrospective case-control study (Correct answer)
- Systematic review
- Cross-sectional prevalence study
Correct answer: Retrospective case-control study
Retrospective case-control studies rely on participants recalling past exposures, making them vulnerable to differential recall between cases and controls.
ATC Evidence-Based Practice 5
A case-control study recruits individuals WITH a condition (cases) and WITHOUT a condition (controls).
This design is BEST for studying: