Fig. 1

Directed Acyclic Graph (DAG) demonstrating the correlation of each variable. Abbreviations: abo, ABO blood group; anesth, duration of anesthesia; anesth techniques, anesthetic techniques; asa, American Society of Anesthesiologists; benzo, premedication with benzodiazepine; bmi, body mass index; dynas, intraoperative use of parecoxib; gaba, preoperative use of gabapentin; intramme, intraoperative use of morphine milligram equivalent; intrketa, intraoperative use of ketamine; intrpara, intraoperative use of paracetamol; ondan, intraoperative use of ondansetron; preanxie, preoperative anxiety score; prega, preoperative use of pregabalin; preverb, preoperative pain score; pt, in or out patient status; relig, religion; reop, reoperation; rrarri, pain score upon postanesthesia care unit arrival; rrmme, morphine milligram equivalent in postanesthesia care unit; rrpara, use of paracetamol in postanesthesia care unit; rrpare, use of parecoxib in postanesthesia care unit; surg, duration of surgery; type of sx, type of operation