Dyads of children and parents allocated to the IG were taken into a tour to a simulation operating room accompanied by an expert anesthesia technologist two weeks before the day of surgery. This simulation operating theater is a real operating room equipped with a surgical trolley, sealing surgical lights, anesthesia machine, vital signs monitor, stethoscope, surgical trays, surgical sink, and gas supply pendent. It was prepared with popular cartoon characters, child manikin, and face masks connected to the anesthesia circuit and re-breathing bag. After being assessed by anesthesia clinic doctors, children and their parents in the IG were given a chance to visit the simulation operating room, to receive orientation, education, and demonstration orientation about what they are going to experience in the operating room. Children were encouraged to apply vital signs monitoring, and to simulate providing mask anesthesia induction to a child manikin.

Dyads assigned to the CG were provided only the standard practice on their day admission to the hospital.

Dyads allocated to the IG were taken into a tour to a simulation operating room accompanied by an expert anesthesia technologist two weeks before the day of surgery. This simulation operating theater is a real operating room equipped with a surgical trolley, sealing surgical lights, anesthesia machine, vital signs monitor, stethoscope, surgical trays, surgical sink, and gas supply pendent. It was prepared with popular cartoon characters, child manikin, and face masks connected to the anesthesia circuit and re-breathing bag. After being assessed by anesthesia clinic doctors, children and their parents in the IG were given a chance to visit the simulation operating room, to receive orientation, education, and demonstration orientation about what they are going to experience in the operating room. Children were encouraged to apply vital signs monitoring, and to simulate providing mask anesthesia induction to a child manikin.

measured using the modified-Yale Pre-Operative Anxiety Scale (m-YPAS). The m-YPAS is an observational anxiety scale used to assess anxiety levels in the preoperative period and during the induction of anesthesia. The total score of the scale ranged from 23 to 100, and the higher score means a worse outcome. The reference point to define high anxiety cases in the preoperative period is 30.

measured using the modified-Yale Pre-Operative Anxiety Scale (m-YPAS). The m-YPAS is an observational anxiety scale used to assess anxiety levels in the preoperative period and during the induction of anesthesia. The total score of the scale ranged from 23 to 100, and the higher score means a worse outcome. The reference point to define high anxiety cases in the preoperative period is 30.

a self-administered questionnaire, Parents' anxiety was assessed using a validated version of Beck Anxiety Inventory Scale (BAIS) into Arabic. The total scale score range from 0 to 63, where a score of 0-9 indicates no anxiety, 10-18 mild anxiety, 19-29 moderate anxiety, and 30-63 severe anxiety.

somatic signs of anxiety, including children's heart rate (HR) were recorded.

the age of child participants measured by years.

the gender of child participants (male, female)