Estimation of risk ratios in case‐base studies with competing risks

Abstract

The case‐base study is a recently developed modification of the case‐control design that leads to risk ratio estimates. Currently available methods for the analysis of case‐base studies lead to estimates of the unconditional risk ratio which may be misleading if censoring occurs. In this manuscript, we describe an approach for the analysis of case‐base studies that yields conditional risk ratio estimates which remain valid in the presence of censoring. The approach we propose for estimating risk ratios and their standard errors involves a non‐iterative procedure.