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What is Incidence rate of lung cancer among smokers is 8 per 1000 and among non smokers is 1 per 1000. Population attibutable risk is - and explain in detail?
It is the incidence of the disease in the total population minus the incidence of disease among those who were not exposed to the suspected causal factor. The concept of population attributable risk is useful in that it provides an estimate of the amount by which the disease could be eliminated or modified (refer pgno:79 park 23 rd edition)