We found a matchYour institution may have access to this item. Find your institution then sign in to continue.TitleInvited commentary: old problem, new wrinkles.AuthorsPotter, J DPublicationAmerican journal of epidemiology, 1998, Vol 147, Issue 10, p911ISSN0002-9262Publication typeJournal ArticleDOI10.1093/oxfordjournals.aje.a009380