Table 2.
Participant characteristics of the training and test set.
| Training sets (n = 917) | Test sets (n = 392) | ||||||
|---|---|---|---|---|---|---|---|
| SF (Mild) (n = 600) |
SF (Moderate/Severe) (n = 317) |
P value (Inner) |
SF (Mild) (n = 254) |
SF (Moderate/Severe) (n = 138) |
P value (Inner) |
P value (External) |
|
| Demographic data | |||||||
| Gender | 0.15 | 0.09 | 0.07 | ||||
| Male | 241 (26.3%) | 112 (12.2%) | 120 (30.6%) | 53 (13.5%) | |||
| Female | 359 (39.2%) | 205 (22.4%) | 134 (34.2%) | 85 (21.7%) | |||
| Age | 58.0 (51.0, 67.0) | 68.0 (59.0, 73.0) | < 0.001 | 59.0 (52.0, 66.0) | 65.0 (58.0, 72.0) | < 0.001 | 0.79 |
| Living area | < 0.001 | < 0.001 | 0.98 | ||||
| Guizhou | 130 (14.2%) | 138 (15.1%) | 57 (14.5%) | 59 (15.1%) | |||
| Shanxi | 194 (21.2%) | 132 (14.4%) | 86 (21.9%) | 51 (13.0%) | |||
| Sichuan | 276 (30.1%) | 47 (5.10%) | 111 (28.3%) | 28 (7.10%) | |||
| Nationality | < 0.001 | 0.01 | 0.34 | ||||
| Han ethnicity | 289 (31.5%) | 311 (33.9%) | 123 (31.4%) | 131 (33.4%) | |||
| Minority | 224 (24.4%) | 93 (10.1%) | 85 (21.7%) | 53 (13.5%) | |||
| Educational level | < 0.001 | 0.009 | 0.72 | ||||
| Illiteracy | 160 (17.5%) | 35 (3.80%) | 69 (17.6%) | 22 (5.60%) | |||
| Elementary school | 296 (32.3%) | 177 (19.3%) | 113 (28.8%) | 82 (20.9%) | |||
| Middle school and above | 144 (15.7%) | 105 (11.5%) | 72 (18.4%) | 34 (8.70%) | |||
| Annual income (Yuan) | < 0.001 | 0.003 | 0.46 | ||||
| Less than 20,000 | 285 (31.1%) | 315 (34.4%) | 110 (28.1%) | 114 (36.7%) | |||
| More than 20,000 | 194 (21.2%) | 123 (13.4%) | 86 (21.9%) | 52 (13.3%) | |||
| Average sleep time (hours) | 8.00 (7.00, 9.00) | 7.00 (6.00, 8.00) | < 0.001 | 8.00 (7.00, 9.00) | 8.00 (6.00, 9.00) | 0.006 | 0.33 |
| Body mass index | 25.4 (23.2, 28.0) | 24.7 (22.5, 27.3) | 0.01 | 25.6 (23.2, 27.9) | 24.9 (22.4, 27.4) | 0.06 | 0.91 |
| Bone density | 1529 (1511, 1550) | 1519 (1505, 1535) | < 0.001 | 1531 (1511, 1557) | 1517 (1505, 1533) | < 0.001 | 0.59 |
| Bone mass index | 48.3 (43.9, 53.6) | 44.8 (41.1, 50.2) | < 0.001 | 48.6 (44.2, 55.4) | 45.7 (41.9, 49.7) | < 0.001 | 0.17 |
| Bone mass | 4.80 (4.40, 5.20) | 4.60 (4.20, 5.20) | < 0.001 | 5.00 (4.40, 5.40) | 4.60 (4.20, 5.00) | 0.002 | 0.31 |
| Orthopedic surgical evaluation | |||||||
| Elbow function | < 0.001 | < 0.001 | 0.10 | ||||
| No limitation of movement | 463 (50.5%) | 137 (14.9%) | 181 (46.2%) | 73 (18.6%) | |||
| Significant limitation of movement | 167 (18.2%) | 150 (16.4%) | 70 (17.9%) | 68 (17.4%) | |||
| Spinal function | < 0.001 | < 0.001 | 0.43 | ||||
| No limitation of movement | 425 (46.4%) | 175 (19.1%) | 174 (44.4%) | 80 (20.4%) | |||
| Significant limitation of movement | 146 (15.9%) | 171 (18.7%) | 61 (15.6%) | 77 (19.6%) | |||
| Knee function | < 0.001 | < 0.001 | 0.32 | ||||
| No limitation of movement | 436 (47.6%) | 164 (17.9%) | 189 (48.2%) | 65 (16.6%) | |||
| Significant limitation of movement | 84 (9.20%) | 234 (25.4%) | 45 (11.5%) | 93 (23.7%) | |||
| Shoulder function | < 0.001 | < 0.001 | 0.07 | ||||
| No limitation of movement | 539 (58.8%) | 61 (6.70%) | 219 (55.9%) | 35 (8.90%) | |||
| Significant limitation of movement | 204 (22.3%) | 113 (12.3%) | 75 (19.1%) | 63 (16.1%) | |||
| Pain level score | 3.00 (2.00, 4.00 ) | 5.00 (4.00, 6.00 ) | < 0.001 | 3.00 (2.00, 4.00) | 5.00 (4.00, 6.00) | < 0.001 | 0.93 |
| Bone metabolism indicators | |||||||
| PTH (pg/mL) | 52.8 (40.8, 67.6) | 48.3 (38.3, 64.1) | 0.002 | 51.6 (38.7, 67.0) | 50.4 (41.0, 65.4) | 0.50 | 0.72 |
| Osteocalcin (ng/mL) | 24.9 (19.2, 33.1) | 28.1 (21.9, 35.7) | 0.003 | 24.5 (18.0, 30.7) | 27.1 (21.5, 34.3) | 0.004 | 0.05 |
| PINP (µg/L) | 77.5 (56.0, 96.3) | 77.8 (61.6, 98.2) | 0.02 | 66.5 (52.1, 88.0) | 74.1 (56.9, 96.3) | 0.01 | 0.03 |
| β-CrossLaps (ng/mL) | 0.450 (0.338, 0.600) | 0.520 (0.390, 0.650) | 0.001 | 0.425 (0.320, 0.570) | 0.530 (0.360, 0.670) | 0.002 | 0.10 |
| Vitamin D (ng/mL) | 23.1 (17.9, 29.1) | 24.3 (19.2, 29.9) | 0.02 | 23.0 (18.2, 29.0) | 25.1 (19.2, 30.6) | 0.06 | 0.64 |
| Biochemical indicators | |||||||
| Total bilirubin (µmol/L) | 11.63 (7.20, 16.4) | 10.0 (6.30, 14.4) | 0.003 | 12.3 (6.72, 18.3) | 10.3 (6.37, 14.0) | 0.03 | 0.46 |
| Direct bilirubin (µmol/L) | 2.93 (2.01, 4.10) | 3.30 (2.45, 4.41) | 0.001 | 3.10 (2.10, 4.26) | 3.20 (2.25, 4.18) | 0.20 | 0.99 |
| Urea (mmol/L) | 5.11 (4.30, 6.20) | 5.50 (4.80, 6.60) | < 0.001 | 5.29 (4.39, 6.42) | 5.47 (4.65, 6.80) | 0.03 | 0.59 |
| IBIL (µmol/L) | 9.60 (5.10, 13.9) | 7.60 (4.20, 11.0) | < 0.001 | 9.40 (5.20, 14.9) | 7.25 (4.13, 10.2) | 0.004 | 0.87 |
| Albumin (g/L) | 44.4 (42.7, 46.0) | 43.7 (41.9, 45.7) | 0.007 | 44.4 (42.3, 46.1) | 44.0 (41.8, 48.5) | 0.19 | 0.69 |
| Urinary fluoride (mg/L) | 1.26 (0.66, 2.61) | 2.04 (1.11, 3.34) | < 0.001 | 1.33 (0.740, 2.91) | 1.83 (0.922, 3.28) | 0.01 | 0.47 |
| WBC (10^9/L) | 5.89 (4.72, 6.94) | 6.21 (5.30, 7.60) | < 0.001 | 6.19 (5.07, 7.30) | 6.15 (5.1, 7.49) | 0.50 | 0.07 |
| NEUT (10^9/L) | 3.50 (2.68, 4.54) | 3.86 (3.05, 5.01) | 0.001 | 3.79 (2.86, 4.79) | 3.81 (2.91, 5.37) | 0.30 | 0.08 |
| RBC (10^12/L) | 4.95 (4.52, 5.42) | 4.65 (4.25, 5.00) | < 0.001 | 4.96 (4.52, 5.46) | 4.64 (4.31, 4.97) | < 0.001 | 0.74 |
| HCT (%) | 45.1 (41.3, 48.9) | 42.7 (39.4, 46.2) | < 0.001 | 45.5 (41.1, 50.1) | 43.2 (40.5, 47.4) | 0.02 | 0.13 |
| MCV (fL) | 91.8 (88.5, 94.9) | 92.2 (89.5, 95.5) | 0.03 | 91.9 (88.5, 94.8) | 92.5 (89.7, 95.5) | 0.06 | 0.79 |
| MCH (pg) | 29.8 (28.4, 31.2) | 30.4 (29.2, 31.8) | < 0.001 | 29.8 (28.4, 31.3) | 30.5 (29.1, 31.9) | 0.004 | 0.88 |
| MCHC (g/dL) | 321 (316, 331) | 329 (323, 336) | < 0.001 | 322 (316, 331) | 328 (319, 334) | 0.003 | 0.83 |
| PDW (fL) | 11.4 (9.90, 15.6) | 14.3 (10.8, 16.4) | < 0.001 | 11.3 (9.90, 15.9) | 13.6 (10.7, 16.3) | 0.006 | 0.64 |
| PCT (%) | 0.240 (0.200, 0.280) | 0.230 (0.190, 0.270) | 0.01 | 0.250 (0.200, 0.290) | 0.230 (0.200, 0.280) | 0.10 | 0.45 |
| IL5 (pg/mL) | 3.22 (2.41, 4.01) | 2.90 (1.23, 3.86) | 0.001 | 3.27 (2.49, 4.14) | 2.63 (1.19, 3.68) | < 0.001 | 0.94 |
| IFNα (pg/mL) | 2.48 (1.76, 3.03) | 2.04 (0.930, 2.85) | < 0.001 | 2.46 (1.81, 3.09) | 1.98 (0.898, 2.71) | < 0.001 | 0.86 |
| IL2 (pg/mL) | 0.920 (0.660, 1.20) | 0.840 (0.380, 1.15) | 0.02 | 0.925 (0.670, 1.27) | 0.760 (0.460, 1.15) | 0.02 | 0.69 |
| IL1β (pg/mL) | 1.83 (0.710, 4.48) | 1.04 (0.180, 4.48) | < 0.001 | 1.88 (0.820, 4.48) | 1.13 (0.210, 4.48) | 0.002 | 0.81 |
| IFNγ (pg/mL) | 4.36 (1.78, 7.27) | 3.07 (0.840, 7.27) | 0.006 | 4.13 (1.79, 7.75) | 2.47 (0.618, 6.58) | 0.002 | 0.85 |
| IL4 (pg/mL) | 0.515 (0.270, 0.913) | 0.570 (0.310, 1.04) | 0.02 | 0.600 (0.320, 0.948) | 0.520 (0.278, 0.855) | 0.38 | 0.69 |
Inner P values compare severity groups within the same dataset; External P values compare the training and test sets. All numerical values in this table are rounded to three significant digits to ensure consistent precision.