Table 2.
Continuous variables contained within the training and validation sets
| Feature | Training set (n = 189) | Validation set (n = 815) | Percent missing | p Value |
|---|---|---|---|---|
| Age at surgery (years) | ||||
| Mean | 62 | 66 | 0 | < 0.001* |
| SD | 14 | 13 | ||
| Median | 63 | 67 | ||
| IQR | 54, 72 | 58, 76 | ||
| Hemoglobin (mg/dL) | ||||
| Mean | 11.5 | 11.5 | 0.6 | 1.0 |
| SD | 1.9 | 3.5 | ||
| Median | 11.4 | 11.3 | ||
| IQR | 10.1, 12.9 | 10.3, 12.6 | ||
| Absolute lymphocyte count (K/μL) | ||||
| Mean | 1.2 | 1.2 | 83.8 | 0.48 |
| SD | 1.3 | 0.74 | ||
| Median | 1.0 | 1.2 | ||
| IQR | 0.6, 1.5 | 0.8, 1.6 | ||
| Surgeon’s estimate of survival (months) | ||||
| Mean | 10 | N/A | 100 | N/A |
| SD | 9 | |||
| Median | 6 | |||
| IQR | 4, 12 | |||
*Distributions are significantly different between training and validation sets by two-tailed Student’s t test; Percent missing = the proportion of unknown or missing data in the validation set; IQR = interquartile range; N/A = not applicable.