Start practicing

Biostatistics & Research · single question

Relative Risk (RR) — what is the definition and in which study is it calculated?

  1. Probability of exposure among diseased vs non-diseased; calculated in case-control studies
  2. Probability of disease among exposed vs non-exposed; calculated in cohort studies
  3. Odds of disease among exposed vs non-exposed; calculated in case-control studies
  4. Association between exposure and outcome; calculated only in RCTs
  5. Incidence of disease in total population; calculated in cross-sectional studies
Show answer and explanation

Correct answer: B. Probability of disease among exposed vs non-exposed; calculated in cohort studies

✓ B) Relative Risk = probability of disease among exposed / probability of disease among non-exposed; calculated in cohort studies.
RR formula: RR = [incidence in exposed] / [incidence in unexposed]. Interpretation: RR>1 = increased risk; RR=1 = no risk difference; RR<1 = reduced risk. Calculated in: retrospective AND prospective cohort studies. Case-control studies use ODDS RATIO (cannot directly calculate incidence in case-control). Cross-sectional studies use prevalence ratio.

Practice Biostatistics & Research questions Biostatistics & Research study notes

More Biostatistics & Research practice questions