[1] Natl Taiwan Univ Hosp, Dept Emergency Med, Taipei 100, Taiwan
[2] Natl Taiwan Univ Hosp, Dept Med Educ, Taipei 100, Taiwan
[3] Natl Taiwan Univ, Coll Med, Dept Primary Care Med, Taipei 10764, Taiwan
[4] Natl Taiwan Univ, Coll Publ Hlth, Grad Inst Epidemiol & Prevent Med, Taipei 10764, Taiwan
[5] Drexel Univ, Coll Med, St Christophers Hosp Children, Dept Pediat, Philadelphia, PA 19104 USA
[6] Univ Calif San Francisco, Dept Pediat, San Francisco, CA USA
[7] Univ Texas Arlington, Coll Nursing, Arlington, TX 76019 USA
[8] N Bristol NHS Trust, Southmead Hosp, Dept Anaesthet & Intens Care, Bristol BS10 5NB, Avon, England