30 min before the induction of anesthesia, chloral hydrate (40 mg/kg) or placebo was administered to the children orally.

Preoperative Anxiety Score

Modified Yale Preoperative Anxiety Scale (YPAS, 0-100) was assessed by observer Anesth Analg 1997;85:783-8

Induction Compliance Checklist

Induction Compliance Checklists (ICC, 0-10) was assessed by anesthetist Anesthesiology 1998;89:1147-56

-Postoperative Pain Score

Face, Legs, Activity, Cry, Consolability (FLACC) Behavioral Scale (0-10) was assessed by observer Am J Crit Care. 2010 Jan;19(1):55-61

Posthospitalization Behavior Questionnaire

Posthospitalization Behavioural Questionnaire (27-135)was sent to all parents of children Paediatr Anaesth. 2001 Nov;11(6):719-23.