Population Attributable Fraction (PAF) is a measure used in epidemiology to estimate the proportion of a disease in a population that can be attributed to a specific risk factor. It helps public health officials understand the impact of that risk factor on the overall health of the community. For example, if smoking is a risk factor for lung cancer, PAF can indicate how many lung cancer cases in a population are linked to smoking. PAF is calculated using data on the prevalence of the risk factor and its association with the disease. This information can guide interventions and policies aimed at reducing the risk factor's prevalence, ultimately improving public health outcomes. By focusing on high PAF factors, health initiatives can effectively target resources to reduce disease burden in the population.