The debate surrounding an observational study rarely centers around the K covariates that have been accounted for through matching, weighting, or some other form of adjustment; rather, a critic's counterclaim typically rests upon the existence of a nettlesome https://www.w3.org/1998/Math/MathML"> K + 1 https://s3-euw1-ap-pe-df-pch-content-public-p.s3.eu-west-1.amazonaws.com/9781003102670/60801d0b-e7e6-4d6c-aa75-7056e29cb275/content/math25_1.tif" xmlns:xlink="https://www.w3.org/1999/xlink"/> st covariate for which the researcher did not account, an unobserved covariate whose relationship with treatment assignment and the outcome of interest may explain away the study's purported finding. Should the totality of evidence assume the absence of hidden bias, as is common with studies proceeding under the usual expedient of strong ignorability, the critic need merely suggest the existence of bias to cast doubt upon the posited causal mechanism. It is thus incumbent upon researchers not only to anticipate such criticism, but also to arm themselves with a suitable rejoinder.
原文链接
分享
引用
