Medical search
relative risk ( RR )
FREE subscriptions for doctors and students... click here
You have 3 more open access pages.
Relative risk is the ratio between the rate of disease in the population exposed to a particular factor and the rate in those not exposed.
- Given the following:
- a = suspected cause present and disease present
- b = suspected cause present and disease absent
- c = suspected cause absent and disease present
- d = suspected cause absent and disease absent
- total disease present = a+c
- total disease absent = b+d
- total suspected cause present = a+b
- total suspected cause absent = c+d
- relative risk (RR) = a / (a+b) divided by the result of c/ (c+d)
If:
the RR =1, or the confidence interval (CI) includes 1, then there is no significant difference between the treatment and control groups
the RR>1 and the CI does not include 1, events are significantly more likely in the treatment group than the control group
the RR<1 and CI does not include 1, events are significantly less likely in the treatment group than the control group
Last reviewed 08/2020
Links: