Table 1.
Distribution of demographic and clinical information.
| Variables | Total population (N = 1,298; 100.0%) |
Training cohort (N = 910; 70.1%) |
Validation cohort (N = 388; 29.9%) |
P | |||
|---|---|---|---|---|---|---|---|
| N | % | N | % | N | % | ||
| Lung metastasis | 0.945 | ||||||
| No | 1,172 | 90.3 | 822 | 90.3 | 350 | 90.2 | |
| Yes | 126 | 9.7 | 88 | 9.7 | 38 | 9.8 | |
| Age (years) | 0.432 | ||||||
| <18 | 197 | 15.2 | 136 | 14.9 | 61 | 15.7 | |
| 18–50 | 476 | 36.7 | 344 | 37.8 | 132 | 34.0 | |
| >50 | 625 | 48.2 | 430 | 47.3 | 195 | 50.3 | |
| Race | 0.115 | ||||||
| White | 1,110 | 85.5 | 789 | 86.7 | 321 | 82.7 | |
| Black | 90 | 6.9 | 55 | 6.0 | 35 | 9.0 | |
| Other | 98 | 7.6 | 66 | 7.3 | 32 | 8.2 | |
| Sex | 0.086 | ||||||
| Male | 779 | 60.0 | 560 | 61.5 | 219 | 56.4 | |
| Female | 519 | 40.0 | 350 | 38.5 | 169 | 43.6 | |
| Year of birth | 0.965 | ||||||
| <1970 | 779 | 60.0 | 548 | 60.2 | 231 | 59.5 | |
| 1970–2000 | 474 | 36.5 | 331 | 36.4 | 143 | 36.9 | |
| >2000 | 45 | 3.5 | 31 | 3.4 | 14 | 3.6 | |
| ICD O 3 histologic type | 0.233 | ||||||
| Osteosarcoma | 239 | 18.4 | 161 | 17.7 | 78 | 20.1 | |
| Chondrosarcoma | 433 | 33.4 | 301 | 33.1 | 132 | 34.0 | |
| Ewing’s sarcoma | 280 | 21.6 | 191 | 21.0 | 89 | 22.9 | |
| Chordoma | 346 | 26.7 | 257 | 28.2 | 89 | 22.9 | |
| Grade | 0.338 | ||||||
| Grade I | 147 | 11.3 | 98 | 10.8 | 49 | 12.6 | |
| Grade II | 188 | 14.5 | 131 | 14.4 | 57 | 14.7 | |
| Grade III | 138 | 10.6 | 90 | 9.9 | 48 | 12.4 | |
| Grade IV | 197 | 15.2 | 135 | 14.8 | 62 | 16.0 | |
| Unknown | 628 | 48.4 | 456 | 50.1 | 172 | 44.3 | |
| Lymph node involvement | 0.245 | ||||||
| No | 1,198 | 92.3 | 845 | 92.9 | 353 | 91.0 | |
| Yes | 100 | 7.7 | 65 | 7.1 | 35 | 9.0 | |
| Other site metastasis | 0.830 | ||||||
| No | 1,147 | 88.4 | 803 | 88.2 | 344 | 88.7 | |
| Yes | 151 | 11.6 | 107 | 11.8 | 44 | 11.3 | |
| Tumor size (cm) | 0.151 | ||||||
| <5 | 267 | 20.6 | 189 | 20.8 | 78 | 20.1 | |
| 5–10 | 545 | 42.0 | 367 | 40.3 | 178 | 45.9 | |
| >10 | 486 | 37.4 | 354 | 38.9 | 132 | 34.0 | |
| Tumor extension | 0.402 | ||||||
| Inside periosteum | 457 | 35.2 | 327 | 35.9 | 130 | 33.5 | |
| Beyond periosteum | 841 | 64.8 | 583 | 64.1 | 258 | 66.5 | |
| Origin laterality | 0.471 | ||||||
| Left | 292 | 22.5 | 204 | 22.4 | 88 | 22.7 | |
| Right | 321 | 24.7 | 217 | 23.8 | 104 | 26.8 | |
| Other | 685 | 52.8 | 489 | 53.7 | 196 | 50.5 | |
| Reporting source | 0.688 | ||||||
| Hospital | 1,275 | 98.2 | 893 | 98.1 | 382 | 98.5 | |
| Other | 23 | 1.8 | 17 | 1.9 | 6 | 1.5 | |
| Insurance | 0.961 | ||||||
| Insured | 843 | 64.9 | 591 | 64.9 | 252 | 64.9 | |
| Medicaid | 165 | 12.7 | 117 | 12.9 | 48 | 12.4 | |
| Other | 290 | 22.3 | 202 | 22.2 | 88 | 22.7 | |
| Marriage | 0.839 | ||||||
| Married | 585 | 45.1 | 417 | 45.8 | 168 | 43.3 | |
| Divorced | 67 | 5.2 | 49 | 5.4 | 18 | 4.6 | |
| Single | 534 | 41.1 | 366 | 40.2 | 168 | 43.3 | |
| Widowed | 62 | 4.8 | 44 | 4.8 | 18 | 4.6 | |
| Other | 50 | 3.9 | 34 | 3.7 | 16 | 4.1 | |
Chi-square test: these values are statistically significant at a p-value <0.05.