We found a matchYour institution may have access to this item. Find your institution then sign in to continue.TitleVariation in patient-sharing networks of physicians across the United States.AuthorsLandon BE; Keating NL; Barnett ML; Onnela JP; Paul S; O'Malley AJ; Keegan T; Christakis NAPublicationJAMA, 2012, Vol 308, Issue 3, p265ISSN1538-3598Publication typearticleDOI10.1001/jama.2012.7615