Table 1 Study population characteristics
Characteristics | Prognostic value1 | Missing, % | Multiple imputed data2 | Complete-case data2 | ||
|---|---|---|---|---|---|---|
Distribution3 | Univariable linear regression model4 | Distribution | Univariable linear regression model | |||
Patient and disease-related factors (N = 18) | ||||||
Age at surgery, in years | 6.5 | 0 | 59 (53, 65) | 0.08 [0.03; 0.12] | 59 (52, 64) | 0.05 [− 0.01; 0.12] |
Male sex | 5 | 0 | 613 (41%) | − 1.93 [− 2.78; − 1.09] | 300 (42%) | − 1.63 [− 2.87; − 0.39] |
Body mass index (BMI), in kg/m2 | 6.5 | 0.7 | 26 (23, 28) | − 0.19 [− 0.29; − 0.1] | 26 (23, 29) | − 0.23 [− 0.37; − 0.08] |
ASA classification | 5 | 0.1 | ||||
I | 383 (25%) | Ref | 176 (25%) | Ref | ||
II | 941 (62%) | − 0.79 [− 1.76; 0.19] | 464 (65%) | − 0.35 [− 1.78; 1.09] | ||
III | 186 (12%) | − 2.91 [− 4.35; − 1.46] | 72 (10%) | − 4.18 [− 6.45; − 1.9] | ||
Dominant side operated | 3 | 0.9 | 1019 (67%) | − 0.36 [− 1.26; 0.54] | 495 (70%) | − 0.96 [− 2.3; 0.37] |
Smoker at surgery | 12.5 | 0.3 | 242 (16%) | − 1.7 [− 2.84; − 0.56] | 107 (15%) | − 2.02 [− 3.73; − 0.31] |
Preoperative medication | 9 | 45.4 | 1105 (73%) | − 0.48 [− 1.69; 0.73] | 563 (79%) | − 0.46 [− 1.97; 1.05] |
Preoperative physiotherapy | 6 | 45.4 | 684 (45%) | − 0.59 [− 1.64; 0.46] | 319 (45%) | − 0.6 [− 1.84; 0.63] |
Preoperative steroid infiltrations | 7.5 | 1.9 | ||||
None | 1193 (79%) | Ref | 445 (63%) | Ref | ||
One | 165 (11%) | − 1.28 [− 2.63; 0.08] | 141 (20%) | − 0.89 [− 2.47; 0.68] | ||
Two or more | 152 (10%) | − 3.28 [− 4.71; − 1.84] | 126 (18%) | − 2.39 [− 4.04; − 0.74] | ||
Traumatic onset | 11 | 0 | 784 (52%) | 0.79 [− 0.05; 1.62] | 374 (53%) | 0.48 [− 0.75; 1.71] |
Symptom duration | 8 | 1.2 | ||||
Less than a month | 157 (10%) | Ref | 69 (9.7%) | Ref | ||
One to 3 months | 286 (19%) | − 0.39 [− 2.01; 1.22] | 122 (17%) | − 0.52 [− 2.98; 1.95] | ||
Three to 6 months | 344 (23%) | − 0.5 [− 2.06; 1.07] | 157 (22%) | − 0.67 [− 3.03; 1.69] | ||
Six months to 1 year | 298 (20%) | − 1.51 [− 3.11; 0.09] | 153 (21%) | − 2.25 [− 4.62; 0.12] | ||
More than a year | 425 (28%) | − 1.69 [− 3.21; − 0.17] | 211 (30%) | − 1.51 [− 3.78; 0.76] | ||
Level of depression and anxiety (EQ-5D-5L) | 12.5 | 1.3 | ||||
Not anxious/depressed | 995 (66%) | Ref | 461 (65%) | Ref | ||
A bit anxious/depressed | 329 (22%) | − 1.97 [− 2.98; − 0.97] | 166 (23%) | − 2.26 [− 3.71; − 0.81] | ||
At least moderately anxious/depressed | 186 (12%) | − 6.38 [− 7.64; − 5.12] | 85 (12%) | − 5.21 [− 7.1; − 3.31] | ||
Baseline constant score | 8 | 29.7 | 58 (44, 68) | 0.11 [0.08; 0.14] | 57 (45, 67) | 0.1 [0.06; 0.13] |
Baseline flexion, in 10-degree unit | 12 | 24.2 | 15 (14, 17) | 0.29 [0.1; 0.47] | 15 (14, 16) | 0.18 [− 0.06; 0.42] |
Baseline abduction, in 10-degree unit | 11 | 24.4 | 15 (12, 16) | 0.17 [0.01; 0.32] | 15 (12, 16) | 0.11 [− 0.09; 0.32] |
Baseline external rotation, in 10-degree unit | 6 | 24.6 | 6 (4, 7) | 0.01 [-0.29; 0.32] | 5 (4, 6) | − 0.05 [− 0.43; 0.33] |
Baseline muscle strength in abduction, in kg | 10 | 25.1 | 4 (1, 7) | 0.23 [0.1; 0.36] | 4 (2, 7) | 0.21 [0.03; 0.38] |
Baseline Oxford Shoulder Score | 15 | 0 | 29 (23, 35) | 0.33 [0.28; 0.38] | 29 (22, 34) | 0.31 [0.24; 0.38] |
Operative findings and details (N = 14) | ||||||
Supraspinatus tear | 6.5 | 0 | 1428 (95%) | 0.62 [− 1.22; 2.46] | 673 (95%) | 1.4 [− 1.3; 4.1] |
Subscapularis tear | 12 | 0 | 485 (32%) | − 0.13 [− 1.03; 0.76] | 218 (31%) | 0.26 [− 1.07; 1.6] |
Infraspinatus tear | 8 | 0 | 404 (27%) | 0.89 [− 0.05; 1.83] | 174 (24%) | 0.65 [− 0.78; 2.08] |
Tear severity (Gerber classification) | 11 | 0 | ||||
Partial tear | 332 (22%) | Ref | 155 (22%) | Ref | ||
Single full tear | 572 (38%) | 0.49 [− 0.63; 1.61] | 283 (40%) | 0.16 [− 1.47; 1.8] | ||
Two or three tendons (only one full) | 314 (21%) | 0.26 [− 1.02; 1.53] | 141 (20%) | − 0.46 [− 2.37; 1.45] | ||
Massive tear | 292 (19%) | 0.77 [− 0.53; 2.07] | 133 (19%) | 1.38 [− 0.56; 3.32] | ||
Level of fatty infiltration | 10 | 26.7 | ||||
Level 0 | 761 (50%) | Ref | 379 (53%) | Ref | ||
Level 1 | 628 (42%) | − 1.56 [− 2.51; − 0.61] | 281 (39%) | − 1.12 [− 2.4; 0.17] | ||
Level 2 | 121 (8.0%) | − 1.57 [− 3.33; 0.19] | 52 (7.3%) | − 1.34 [− 3.76; 1.09] | ||
Tendon degeneration | 7 | 0 | 839 (56%) | 0.16 [− 0.68; 1] | 372 (52%) | 0.27 [− 0.96; 1.5] |
Tendon delamination | 7.5 | 0 | 520 (34%) | − 1.22 [− 2.1; − 0.35] | 258 (36%) | − 0.85 [− 2.13; 0.42] |
Operation duration, in minutes | 8 | 0.1 | 75 (60, 94) | − 0.02 [− 0.04; − 0.01] | 73 (59, 94) | − 0.03 [− 0.06; − 0.01] |
Number of anchors used | 7 | 0 | ||||
0–2 | 238 (16%) | Ref | 114 (16%) | Ref | ||
3–4 | 1069 (71%) | − 0.06 [− 1.23; 1.1] | 488 (69%) | − 1.01 [− 2.71; 0.7] | ||
5 + | 203 (13%) | − 0.23 [− 1.78; 1.32] | 110 (15%) | − 0.24 [− 2.43; 1.95] | ||
Number of threads | 7 | 0 | 4 (2, 5) | 0.14 [− 0.09; 0.37] | 3 (2, 4) | 0.26 [− 0.09; 0.61] |
Acromioclavicular joint resection | 2 | 0 | 323 (21%) | − 1.76 [− 2.78; − 0.75] | 139 (20%) | − 1.7 [− 3.25; − 0.16] |
Acromioplasty | 4 | 0 | 1365 (90%) | 1.03 [− 0.38; 2.45] | 643 (90%) | − 0.19 [− 2.26; 1.89] |
Capsulotomy | 8 | 0 | 116 (7.7%) | − 0.45 [− 2.02; 1.12] | 66 (9.3%) | − 0.06 [− 2.18; 2.05] |
Biceps status & treatment | 6 | 0 | ||||
No treatment | 236 (16%) | Ref | 110 (15%) | Ref | ||
Tenotomy | 287 (19%) | − 2.02 [− 3.44; − 0.6] | 175 (25%) | − 1.52 [− 3.5; 0.47] | ||
Tenodesis | 877 (58%) | 0.21 [− 0.97; 1.39] | 391 (55%) | 0.48 [− 1.29; 2.24] | ||
Already ruptured/treated | 110 (7.3%) | − 0.24 [− 2.11; 1.62] | 36 (5.1%) | 0.06 [− 3.08; 3.2] | ||
6-month Oxford Shoulder Score | 43 (37, 46) | 42 (37, 45) | ||||