RecruitingPhase 3Drug trialEvaluation of Analgesia for Spine Fusion Elective Surgery in ChildrenThe multicenter PRECISE Analgesia (Prospective Randomized Evaluation of Analgesia for Idiopathic Scoliosis Spine Fusion Elective Surgery in Children) trials will a) implement and investigate the efficacy and safety of multidose methadone-based standardized enhanced recovery after surgery (ERAS) protocol, and b) develop personalized ERAS protocols including precision methadone and oxycodone dosing and c) personalized analgesia for the safe and effective opioid-sparing management of surgical pain after posterior spine fusion (PSF) in children.