[1] Mahidol Univ, Ramathibodi Hosp, Fac Med, Dept Med, Bangkok, Thailand
[2] Mahidol Univ, Ramathibodi Hosp, Fac Med, Dept Clin Epidemiol & Biostat, Bangkok, Thailand
[3] Mahidol Univ, Chakri Naruebodindra Med Inst, Fac Med, Ramathibodi Hosp, Samut Prakan, Thailand