Demographic characteristics of 2180 participating patients
| Variables | Total (n=2180) | No moderate-severe pain within 24 hours (n=1997) | Moderate-severe pain within 24 hours (n=183) | P values |
| Gender, n (%) | 0.15 | |||
| Male | 1265 (58.0) | 1168 (58.5) | 97 (53) | |
| Female | 915 (42.0) | 829 (41.5) | 86 (47) | |
| Age (years) | 55.4±11.5 | 55.8±11.3 | 51.1±12.5 | <0.001 |
| BMI (kg/m2) | 23.7±3.4 | 23.8±3.4 | 23.2±2.9 | 0.018 |
| ASA | 0.023 | |||
| I | 49 (2.2) | 44 (2.2) | 5 (2.7) | |
| II | 1755 (80.5) | 1596 (79.9) | 159 (86.9) | |
| III | 376 (17.2) | 357 (17.9) | 19 (10.4) | |
| Smoking, n (%) | 0.4 | |||
| No | 1391 (63.8) | 1269 (63.5) | 122 (66.7) | |
| Yes | 789 (36.2) | 728 (36.5) | 61 (33.3) | |
| Education level, n (%) | 0.429 | |||
| Preliminary school | 968 (44.4) | 895 (44.8) | 73 (39.9) | |
| Middle school | 762 (35.0) | 696 (34.9) | 66 (36.1) | |
| College degree | 176 (8.1) | 157 (7.9) | 19 (10.4) | |
| Bachelor degree | 105 (4.8) | 98 (4.9) | 7 (3.8) | |
| Postgraduate degree | 169 (7.8) | 151 (7.6) | 18 (9.8) | |
| History of anaesthesia, n (%) | 0.014 | |||
| No | 1161 (53.3) | 1056 (52.9) | 105 (57.4) | |
| Yes | 805 (36.9) | 753 (37.7) | 52 (28.4) | |
| NA | 214 (9.8) | 188 (9.4) | 26 (14.2) | |
| Hypertension, n (%) | 0.005 | |||
| No | 1688 (77.4) | 1531 (76.7) | 157 (85.8) | |
| Yes | 492 (22.6) | 466 (23.3) | 26 (14.2) | |
| Diabetes, n (%) | 0.133 | |||
| No | 1900 (87.2) | 1734 (86.8) | 166 (90.7) | |
| Yes | 280 (12.8) | 263 (13.2) | 17 (9.3) | |
| Coronary artery disease, n (%) | 0.253 | |||
| No | 2099 (96.3) | 1920 (96.1) | 179 (97.8) | |
| Yes | 81 (3.7) | 77 (3.9) | 4 (2.2) | |
| Cerebral complication, n (%) | 0.605 | |||
| No | 2106 (96.6) | 1928 (96.5) | 178 (97.3) | |
| Yes | 74 (3.4) | 69 (3.5) | 5 (2.7) | |
ASA, American Society of Anesthesiologists; BMI, body mass index.