Predicting Postoperative Vomiting for Orthopedic Patients Receiving Patient-Controlled Epidural Analgesia with the Application of an Artificial Neural Network

Table 1

Variables used for training of the LR and ANN model.

Variable	Coding
Age	Years
Gender	1: female; 0: male
Height	cm
Weight	kg
BMI	Body mass index
Length (catheter length in the epidural space)	cm
Bolus dose	mL
Total knee replacement (TKA)	0: not TKA*; 1: TKA
Epidural level (insertion site of EA catheter)	0: above L4; 1: below L4

∗Other lower extremities surgery.