[1] Kurume Univ, Sch Med, Dept Pediat & Child Hlth, Kurume, Fukuoka 8300011, Japan
[2] St Lukes Int Hosp, Dept Pediat, Tokyo, Japan
[3] Ehime Prefectural Cent Hosp, Childrens Med Ctr, Matsuyama, Ehime, Japan
[4] Ehime Univ, Sch Med, Dept Pediat, Toon, Japan
[5] Kyushu Natl Canc Ctr, Dept Pediat, Fukuoka, Japan
[6] Niigata Canc Ctr Hosp, Dept Pediat, Niigata, Japan
[7] Nagoya Med Ctr, Natl Hosp Org, Dept Pediat, Nagoya, Aichi, Japan
[8] Juntendo Univ, Sch Med, Dept Publ Hlth, Tokyo 113, Japan
[9] Shikoku Med Ctr Children & Adults, Dept Hematooncol, Zentsuji, Japan
[10] Univ Tokyo, Dept Family Nursing, Tokyo, Japan
[11] Natl Res Inst Child Hlth & Dev, Dept Hlth Policy, Tokyo, Japan
[12] Nagoya Med Ctr, Natl Hosp Org, Clin Res Ctr, Nagoya, Aichi, Japan