Table 1.
Descriptive statistics of the study population (n = 6,803)
| Hip arthroplasty patients | pb | Knee arthroplasty patients | pb | |||
|---|---|---|---|---|---|---|
| men (N = 1,627) | women (N = 2,066) | men (N = 1,430) | women (N = 1,680) | |||
| Age | ||||||
| mean (SD) | 65.18 (10.54) | 66.24 (10.59) | 0.003 | 66.06 (9.19) | 65.99 (9.26) | 0.843 |
| BMIa | ||||||
| Underweight | 0 (0%) | 20 (0.97%) | < 0.001 | 2 (0.14%) | 4 (0.24%) | < 0.001 |
| Normal | 379 (23.29%) | 786 (38.04%) | 191 (13.36%) | 286 (17.02%) | ||
| Overweight | 742 (45.61%) | 674 (32.62%) | 637 (44.55%) | 547 (32.56%) | ||
| Obese | 506 (31.10%) | 586 (28.36%) | 600 (41.96%) | 843 (50.18%) | ||
| Education | ||||||
| No school degree | 6 (0.37%) | 9 (0.44%) | < 0.001 | 6 (0.42%) | 12 (0.71%) | < 0.001 |
| Primary school degree | 222 (13.64%) | 270 (13.07%) | 266 (18.60%) | 268 (15.95%) | ||
| High/middle school degree | 831 (51.08%) | 1,287 (62.29%) | 766 (53.57%) | 1,093 (65.06%) | ||
| University degree | 568 (34.91%) | 500 (24.20%) | 392 (27.41%) | 307 (18.27%) | ||
| Living situation | ||||||
| Alone | 220 (13.52%) | 624 (30.20%) | < 0.001 | 172 (12.03%) | 427 (25.42%) | < 0.001 |
| Care facility | 3 (0.18%) | 8 (0.39%) | 7 (0.49%) | 12 (0.71%) | ||
| With a partner/family/friends | 1,392 (85.56%) | 1,423 (68.88%) | 1,247 (87.20%) | 1,225 (72.92%) | ||
| Other | 12 (0.74%) | 11 (0.53%) | 4 (0.28%) | 16 (0.95%) | ||
| Job | ||||||
| Working | 579 (35.59%) | 621 (30.06%) | < 0.001 | 475 (33.22%) | 447 (26.61%) | < 0.001 |
| Voluntarily not working including retirement | 866 (53.23%) | 1230 (59.54%) | 772 (53.99%) | 1,018 (60.60%) | ||
| Looking for work | 18 (1.11%) | 17 (0.82%) | 15 (1.05%) | 19 (1.13%) | ||
| Unable to work | 164 (10.08%) | 198 (9.58%) | 168 (11.75%) | 196 (11.67%) | ||
| Admission PROc mean (SD) | ||||||
| EQ-5D-5L | 0.644 (0.239) | 0.562 (0.269) | < 0.001 | 0.665 (0.230) | 0.589 (0.262) | < 0.001 |
| EQ-VAS | 59.14 (19.90) | 54.96 (19.67) | < 0.001 | 61.09 (19.29) | 55.91 (18.92) | < 0.001 |
| HOOS-PS/ KOOS-PS | 44.29 (15.50) | 50.43 (16.00) | < 0.001 | 40.62 (12.67) | 45.13 (12.35) | < 0.001 |
| PROMIS-D-SF | 47.96 (7.78) | 51.20 (8.40) | < 0.001 | 47.42 (7.69) | 51.04 (8.39) | < 0.001 |
| PROMIS-F-SF | 46.92 (9.20) | 50.97 (10.00) | < 0.001 | 46.28 (9.51) | 49.98 (9.80) | < 0.001 |
| Pain in joint | 6.09 (2.19) | 6.72 (2.05) | < 0.001 | 6.49 (2.04) | 7.04 (1.93) | < 0.001 |
aBMI body mass index
bfor continuous variables a two-sided t-test was performed, for and categorical variables a Chi-square test was performed and for the PRO-scores at admission, a Mann–Whitney U test
cPRO Patient-reported Outcome. The score ranges are: -0.661 to 1.0 for the EQ-5D-5L, 0–100 for the EQ-VAS, HOOS-PS and KOOS-PS, 33.7–75.8 for the PROMIS-F-SF, 41–79.4 for the PROMIS-D-SF and 0–10 for pain. The EQ-5D-5L is reported with three digits after the decimal point due to the small score range