[1] Tufts Univ, Sch Med, Dept Internal Med, Baystate Med Ctr, Springfield, MA 01199 USA
[2] Tufts Univ, Sch Med, Ctr Qual Care Res, Baystate Med Ctr, Springfield, MA 01199 USA
[3] Univ Massachusetts, Sch Med, Meyers Primary Care Inst, Worcester, MA USA
[4] Mayo Clin, Knowledge & Evaluat Res Unit, Div Cardiovasc Dis, Rochester, MN USA
[5] Cleveland Clin, Inst Med, Dept Internal Med, Cleveland, OH 44106 USA