Difference b w the incidence in exposed and non exposed group is best given by
attributable risk : Attributable Risk(AR) (sometimes called Attributable Propoion or Attributable Fraction) is a measure of the prevalence of a condition or disease. Given a group of people exposed to a risk, it&;s the fraction who develop a disease or condition. ref : park 21st ed
relative risk
attributable risk
population attributable risk
odd's ratio
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