[1] Harvard TH Chan Sch Publ Hlth, Dept Social & Behav Sci, Boston, MA USA
[2] Yonsei Univ, Coll Med, Inst Hlth Serv Res, Seoul, South Korea
[3] Yonsei Univ, Coll Nursing, Mo Im Kim Nursing Res Inst, Seoul, South Korea
[4] Cincinnati Childrens Hosp Med Ctr, Dept Pediat, Cincinnati, OH USA
[5] Harvard Med Sch, Boston, MA USA
[6] Yonsei Univ, Coll Med, Dept Prevent Med & Publ Hlth, Seoul, South Korea
[7] Yonsei Univ, Coll Nursing, Brain Korea 21 Four Project, Seoul, South Korea
[8] Yonsei Univ, Coll Nursing, Mo Im Kim Nursing Res Inst, 50-1 Yonsei Ro, Seoul 03722, South Korea