[1] Univ Minnesota, Div Hlth Policy & Management, Minneapolis, MN USA
[2] Univ Wisconsin, Sch Med & Publ Hlth, Madison, WI 53706 USA
[3] HealthPartners Res Fdn, Minneapolis, MN USA
[4] US Dept Vet Affairs, William S Middleton Hosp, Madison, WI USA
[5] Univ Wisconsin, Dept Med, Geriatr Sect, Madison, WI 53706 USA
[6] Univ Minnesota, Div Epidemiol & Community Hlth, Minneapolis, MN USA