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9.2.2  Effect measures for dichotomous outcomes

Introductory text

Box 9.2.a: Calculation of risk ratio (RR), odds ratio (OR) and risk difference (RD) from a 2ยด2 table  Risk and odds  Measures of relative effect: the risk ratio and odds ratio  Warning: OR and RR are not the same  Measures of absolute effect: the risk difference  What is the event?