Table 1.
Distribution of patient, anesthetic, and surgery characteristics between training and test datasets
| Variable | Training set (n=1670) | Test set (n=835) | p Value |
| Duration (h) | 2.8±1.0 | 2.8±1.0 | 0.92 |
| Surgery type (%) | 0.10 | ||
| Hysteroscopy | 25.7 | 27.8 | |
| Breast biopsy/lumpectomy | 25.5 | 23.6 | |
| Pelviscopy/myomectomy | 18.5 | 19.7 | |
| Inguinal and other hernia | 14.9 | 14.8 | |
| Breast plastics | 5.6 | 5.2 | |
| Laparoscopic cholecystectomy | 5.2 | 3.7 | |
| Tubal ligation | 3.4 | 3.5 | |
| Other gyn surgery | 1.3 | 1.8 | |
| Age (decade) | 4.8±1.4 | 4.9±1.3 | 0.26 |
| Sex (% female) | 87.8 | 88.6 | 0.60 |
| Weight (kg) | 69.3±14.4 | 69.5±14.7 | 0.73 |
| History of PONV (%) | 25.4 | 23.2 | 0.26 |
| History of motion sickness (%) | 32.3 | 32.3 | 1.00 |
| Smoker (%) | 10.2 | 11.6 | 0.27 |
| Type of anesthesia (%) | 0.35 | ||
| Intravenous induction with inhalational agent and N2O maintenance | 22.3 | 24.1 | |
| Intravenous induction with inhalational agent maintenance (no N2O) | 34.8 | 32.9 | |
| Inhalation induction with inhalational agent and N2O maintenance | 11.5 | 12.3 | |
| Inhalation induction with inhalational agent maintenance (no N2O) | 5.5 | 6.0 | |
| Intravenous induction and intravenous anesthetic maintenance | 2.0 | 1.0 | |
| Monitored anesthesia care | 24.0 | 23.7 | |
| Prophylactic ondansetron (%) | 47.5 | 47.9 | 0.87 |
| Prophylactic dexamethasone (%) | 41.3 | 39.0 | 0.30 |
| Preoperative or intraoperative application of scopolamine patch (%) | 17.3 | 17.3 | 1.00 |
| Intraoperative metoclopramide =10 mg (%) | 54.8 | 55.2 | 0.86 |
| Intraoperative metoclopramide >10 mg (%) | 2.5 | 4.7 | 0.003 |
| Prophylactic IM ephedrine (%) | 4.0 | 5.5 | 0.10 |
| Intraoperative fentanyl dose (μg) | 91.7±80.0 | 87.8±79.7 | 0.25 |
| Maximum pain score in phase 1 | 3.3±2.4 | 3.3±2.5 | 0.77 |
| Postoperative opioids (analgesic equivalent) | 0.32±0.42 | 0.29±0.37 | 0.08 |
| Crude PONV rate (%) | 22.6 | 22.2 | 0.84 |
| Average number of postoperative rescue anti-emetics given | 0.22±0.61 | 0.21±0.59 | 0.71 |
None of the variables had statistically significant differences between these sets (p>0.05). p Value indicates the result of a χ2 test for categorical variables or of a t test for continuous variables.
gyn, gynecological; IM, intramuscular; PONV, postoperative nausea and vomiting.