We found a matchYour institution may have access to this item. Find your institution then sign in to continue.TitleFallibility in estimating direct effects.AuthorsCole SR; Hernán MAPublicationInternational journal of epidemiology, 2002, Vol 31, Issue 1, p163ISSN0300-5771Publication typearticleDOI10.1093/ije/31.1.163