Risk Ratio/Relative Risk (RR)
Risk Ratio or Relative Risk: The ratio between the probability to fall ill in an exposed and a non-exposed group of persons who were examined in a cohort study.
- With an RR of 1 there is no difference between the two groups.
- With RR less than 1 the risk is lower in the exposed group, with RR higher than1 higher than in the non-exposed group.
By means of significance test it can be investigated how statistically significant this difference is.