Estimation of Attributable Risk in the Presence of Confounding

Abstract LEVIN's attributable risk due to a risk factor is estimated in the presence of confounding in the retrospective study context. The crude attributable risk is decomposed into the attributable risk due to a risk factor and a bias factor which is shown to vanish only when the confounding factor is unassociated to either the risk factor or the Disease or to both. Asymptotic tests are provided for testing interaction, and an appropriate pooled estimate is derived when constancy of partial attributable risks prevails over the levels of the confounding factor.