Factors maintained in the Cox model backward elimination ordered by partial R2 values; the concordance index is shown for both the learning (n=453) and testing samples (n=907)
| Factor | Partial R2 from learning sample | c index, learning sample (n=503) | c index, testing sample (n=1008) |
|---|---|---|---|
| The blank row indicates the point where the concordance index stopped increasing in the testing sample. Factors above this were maintained in the final model while factors below this were dropped. | |||
| *Respondents were asked whether their workplace had made any offers of special arrangements to help them return to work. | |||
| Functional status (4 week) | 9.2 | 0.6489 | 0.6427 |
| Part of body | 1.5 | 0.6533 | 0.6456 |
| Change in pain grade | 2.0 | 0.6703 | 0.6616 |
| Workplace offers* | 3.4 | 0.6830 | 0.6738 |
| Change in pain grade × workplace offers* | 2.3 | 0.6870 | 0.6764 |
| Poor recovery expectations | 2.6 | 0.6955 | 0.6829 |
| Household income ⩾$60K Cdn | 1.04 | 0.6963 | 0.6816 |
| Divorced/widowed | 1.04 | 0.7006 | 0.6815 |
| Filing a claim affect job/negative supervisor reaction | 0.97 | 0.7036 | 0.6826 |