CFO Research Methods & Evidence-Based Practice 2 — Questions and Answers
Question 1: In evidence-based practice, a systematic review differs from a narrative review primarily because it:
- Relies on expert opinion to summarize evidence
- Uses explicit, reproducible methods to identify and appraise studies (Correct answer)
- Focuses exclusively on randomized controlled trials
- Is conducted by a single author to minimize bias
Correct answer: Uses explicit, reproducible methods to identify and appraise studies
Systematic reviews use predefined, transparent methods for searching, selecting, and critically appraising studies to minimize bias.
Question 2: A patient-reported outcome measure (PROM) used in orthotic research is best described as:
- A clinician-rated scale of functional improvement
- A standardized questionnaire completed by the patient about their own health status (Correct answer)
- A biomechanical gait analysis protocol
- A radiographic measurement of deformity correction
Correct answer: A standardized questionnaire completed by the patient about their own health status
PROMs capture the patient's perspective on their own functional status, symptoms, or quality of life.
Question 3: Which type of bias occurs when study participants who drop out differ systematically from those who complete the trial?
- Selection bias
- Attrition bias (Correct answer)
- Detection bias
- Performance bias
Correct answer: Attrition bias
Attrition bias arises when differential dropout between groups affects the validity of results.
Question 4: The Minimal Clinically Important Difference (MCID) in orthotic outcome research represents:
- The smallest change detectable by a measuring instrument
- The smallest change in a score that patients perceive as meaningful (Correct answer)
- The threshold for statistical significance in a clinical trial
- The maximum score achievable on a functional scale
Correct answer: The smallest change in a score that patients perceive as meaningful
MCID is the smallest change in an outcome measure that patients perceive as beneficial, distinguishing statistical from clinical significance.
Question 5: A cross-over study design in orthotic research means that:
- Participants are randomized into two separate groups that never interchange
- Each participant receives both the experimental orthosis and the control condition at different time points (Correct answer)
- The researcher crosses over between different patient populations
- Outcome assessors switch roles between treatment and control groups
Correct answer: Each participant receives both the experimental orthosis and the control condition at different time points
In a crossover design, each participant acts as their own control by receiving both interventions sequentially.
Question 6: Intention-to-treat (ITT) analysis in a clinical trial requires that:
- Only protocol-compliant participants are included in the final analysis
- All randomized participants are analyzed in their originally assigned groups regardless of adherence (Correct answer)
- Participants who cross over are excluded from analysis
- Data are analyzed only after confirming treatment compliance
Correct answer: All randomized participants are analyzed in their originally assigned groups regardless of adherence
ITT preserves the benefits of randomization by analyzing all participants as originally assigned, reflecting real-world effectiveness.
Question 7: When grading the quality of evidence using the GRADE system, which factor would DOWNGRADE the certainty of evidence?
- Large sample size with consistent results
- Imprecision due to wide confidence intervals (Correct answer)
- Blinding of both participants and outcome assessors
- Publication in a peer-reviewed journal
Correct answer: Imprecision due to wide confidence intervals
Wide confidence intervals indicate imprecision, which is one of the five reasons GRADE uses to downgrade certainty of evidence.
CFO Research Methods & Evidence-Based Practice 2
In evidence-based practice, a systematic review differs from a narrative review primarily because it: