From a public health perspective, it is more useful to re-define the attributable risk in terms of the whole population. This modified measure is call the population attributable risk (PAR).

Instead of comparing the outcomes for those with and without a risk factor, (as it is done for statistical testing and AR), the PAR compares the outcomes for the whole population to those without the risk factor.

Attributable risk percent (AR%) - converts the AR into the percent of adverse outcomes preventable in the group with the risk factor.

PAR% - converts the population attributable risk into the percent of adverse outcomes preventable in the entire population at risk.