Summary of TKR study characteristics
| Overall | 3 months | 6 months | 12 months | 24 months | |
| Number of study cohorts | 68 | 15 | 28 | 36 | 10 |
| Total sample sizes | 598 498 | 2503 | 550 928 | 36 157 | 13 953 |
| Median sample size (IQR) | 235 (113.5–580.75) | 116 (95–184) | 197 (111.25–297) | 254.5 (115.5–593.75) | 396.5 (251.75–692.75) |
| Baseline time period range | 1993–2023 | 1998–2023 | 1993–2023 | 1993–2020 | 1993–2019 |
| Mean age (SD) | 69.6 (9.4) (n=52*) | 68.8 (9.2) (n=13*) | 69.6 (9.4) (n=24*) | 68.1 (9.1) (n=26*) | 70 (9.3) (n=6*) |
| Age range | 18–98 (n=24) | 18–90 (n=7) | 18–94 (n=9) | 25–98 (n=14) | 28–90 (n=4) |
| Median % women (IQR) | 63 (58–69.45) | 66.1 (62.35–77.55) | 65.55 (57.65–72.475) | 61.2 (56.95–65.85) | 63 (61.03–64.75) |
| Primary pain outcome reported | |||||
| VAS/NRS pain | 29 | 9 | 16 | 13 | 2 |
| WOMAC pain | 13 | 1 | 4 | 7 | 3 |
| OKS pain | 7 | 1 | 2 | 5 | 1 |
| KOOS pain | 6 | 1 | 1 | 4 | 1 |
| BPI | 3 | 1 | 2 | 2 | 0 |
| KSS/IKSS pain | 2 | 0 | 0 | 2 | 1 |
| EQ-5D 5L pain/discomfort | 1 | 0 | 1 | 0 | 0 |
| Pain disturbing sleep | 1 | 1 | 0 | 1 | 0 |
| Author own question | 6 | 1 | 2 | 2 | 2 |
| Setting | |||||
| Single hospital | 39 | 8 | 16 | 20 | 9 |
| Multiple hospitals | 18 | 0 | 6 | 12 | 1 |
| Multiple surgeons | 4 | 3 | 1 | 1 | 0 |
| Single surgeon | 3 | 3 | 2 | 2 | 0 |
| National registry | 2 | 0 | 1 | 1 | 0 |
| Health region | 1 | 0 | 1 | 0 | 0 |
| Rehabilitation service | 1 | 1 | 1 | 0 | 0 |
| Country | |||||
| Australia | 2 | 0 | 1 | 1 | 1 |
| USA | 17 | 2 | 8 | 5 | 4 |
| UK | 9 | 2 | 3 | 7 | 2 |
| Spain | 5 | 2 | 3 | 2 | 0 |
| Denmark | 5 | 1 | 0 | 5 | 0 |
| France | 4 | 1 | 3 | 2 | 0 |
| Sweden | 3 | 0 | 0 | 2 | 1 |
| China | 3 | 1 | 1 | 0 | 1 |
| Belgium | 2 | 2 | 1 | 1 | 0 |
| Canada | 2 | 0 | 1 | 1 | 0 |
| Finland | 2 | 1 | 0 | 0 | 1 |
| Japan | 2 | 1 | 2 | 1 | 0 |
| Singapore | 2 | 0 | 2 | 1 | 0 |
| South Korea | 2 | 2 | 0 | 1 | 0 |
| The Netherlands | 2 | 0 | 1 | 2 | 0 |
| Hungary | 1 | 0 | 0 | 1 | 0 |
| Italy | 1 | 0 | 0 | 1 | 0 |
| New Zealand | 1 | 0 | 1 | 1 | 0 |
| Norway | 1 | 0 | 0 | 1 | 0 |
| Poland | 1 | 0 | 1 | 0 | 0 |
| Russia | 1 | 0 | 0 | 1 | 0 |
*Only studies reported both mean and SD.
BPI, Brief Pain Inventory; EQ-5D 5L, EuroQol-5 Dimensions-5 Level; KOOS, Knee injury and Osteoarthritis Outcome Score; KSS/IKSS, Knee Society Scores if patient generated; NRS, Numerical Rating Scale; OKS, Oxford Knee Score; TKR, total knee replacement; VAS, Visual Analogue Scale; WOMAC, Western Ontario and McMasters Universities Osteoarthritis Index.