FACEM Research and Innovation 3 — Questions and Answers
Question 1: A study reports a relative risk reduction (RRR) of 50% but an absolute risk reduction (ARR) of only 1%. Which statement best contextualizes this finding?
- The treatment has a clinically large effect because RRR is 50%
- The ARR indicates the absolute benefit is small despite the large RRR (Correct answer)
- The NNT would be 2, indicating high efficacy
- RRR is always more meaningful than ARR for clinical decisions
Correct answer: The ARR indicates the absolute benefit is small despite the large RRR
A large RRR can be misleading when baseline risk is low; ARR of 1% means NNT = 100, indicating modest absolute benefit.
Question 2: Which type of bias occurs when patients with more severe illness are more likely to be selected for a new treatment?
- Recall bias
- Confounding by indication (Correct answer)
- Detection bias
- Attrition bias
Correct answer: Confounding by indication
Confounding by indication occurs when the indication for treatment is also a risk factor for the outcome, distorting observational results.
Question 3: In emergency medicine research, which method is commonly used to obtain consent when patients lack decision-making capacity?
- Waiver of consent approved by an ethics committee (Correct answer)
- Verbal assent from the treating physician
- Written consent from the hospital administrator
- Retrospective consent after treatment
Correct answer: Waiver of consent approved by an ethics committee
A waiver of consent may be granted by an ethics committee for emergency research when the condition precludes consent and delay would harm participants.
Question 4: A p-value of 0.03 means:
- There is a 3% chance the treatment works
- The probability of observing this result by chance alone, assuming no true effect, is 3% (Correct answer)
- The study has 97% power
- The effect size is clinically significant
Correct answer: The probability of observing this result by chance alone, assuming no true effect, is 3%
A p-value is the probability of obtaining results at least as extreme as observed, assuming the null hypothesis is true.
Question 5: The 'intention-to-treat' (ITT) principle in RCT analysis means:
- Participants are analyzed only if they completed the full protocol
- All randomized participants are analyzed in their assigned group regardless of adherence (Correct answer)
- Participants who withdrew are excluded from analysis
- The primary outcome is analyzed by the treating clinician
Correct answer: All randomized participants are analyzed in their assigned group regardless of adherence
ITT analysis preserves the benefits of randomization and avoids bias from differential dropout by analyzing all participants as allocated.
Question 6: Which of the following best defines 'validity' in the context of a research study?
- The consistency of results on repeated measurement
- The degree to which a study measures what it intends to measure (Correct answer)
- The generalizability of findings to other populations
- The statistical precision of the estimate
Correct answer: The degree to which a study measures what it intends to measure
Validity refers to whether a study's methods accurately capture the true construct of interest, distinguishing it from reliability (consistency).
Question 7: In qualitative emergency medicine research, 'saturation' refers to:
- Achieving a statistically significant sample size
- The point at which additional data collection yields no new themes (Correct answer)
- Including participants from all demographic groups
- Completing the maximum number of interviews planned
Correct answer: The point at which additional data collection yields no new themes
Theoretical saturation is reached when further data collection and analysis no longer produce new insights or themes.
FACEM Research and Innovation 3
A study reports a relative risk reduction (RRR) of 50% but an absolute risk reduction (ARR) of only 1%.
Which statement best contextualizes this finding?