[1] Univ N Carolina, Sch Med, Chapel Hill, NC 27515 USA
[2] Rutgers State Univ, Inst Hlth Hlth Care Policy & Aging Res, New Brunswick, NJ 08903 USA
[3] Virginia Polytech Inst & State Univ, Dept Human Dev & Family Sci, Blacksburg, VI USA
[4] Rutgers State Univ, Sch Nursing, New Brunswick, NJ 08903 USA
[5] Renmin Univ China, Sch Lab & Human Resources, Dept Social Secur, Beijing, Peoples R China