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Table 3 Concordance (c-index), R squared as each variable is added into the model

From: Predictors of return to work following motor vehicle related orthopaedic trauma

Factor R-squared C-index
Recovery expectations for usual activities 0.087 0.605
Occupation skill levela 0.104 0.643
New injury severity score 0.121 0.656
Self-assessed pre-injury health statusb 0.154 0.662
Work hours before injuryc 0.177 0.671
Smoking history 0.194 0.678
Education skill levela 0.197 0.679
Recovery expectations for work 0.206 0.687
Injury severity score 0.212 0.687
Total yearly household incomed 0.225 0.695
Self-reported at fault 0.227 0.695
Language other than English 0.240 0.699
Crash on public road 0.241 0.700
Risk of short term harm due to alcohol consumptione 0.244 0.700
Age 0.251 0.704
Sex 0.252 0.707
  1. The blank row indicates the point where the concordance index plateaus Factors above this were maintained while factors below this were dropped
  2. aMeasures for occupation and education are from the Australian Standard Classification of Occupations (ASCO), Cat. No. 1220.0, Australian Bureau of Statistics 1997 and the Australian Standard Classification of Education (ASCED), Cat. No. 1272.0, Australian Bureau of Statistics 2001
  3. bSelf-assessed health status is based on Question 1 from the Short Form 36, version 2, (SF36v2)
  4. cMeasures for full-time (usually working at least 35 hours per week) and part-time (usually working 1–35 hours per week) are from the Australian Health Survey: Users' Guide, 2011–13, Cat. No. 4363.0.55.001, Australian Bureau of Statistics
  5. dCategories of income are from the Household, Income and Labour Dynamics in Australia (HILDA) Survey Wave 6 Household Questionnaire.
  6. eQuestions to determine risk of harm were from the Alcohol Use Disorders Identification Test: Self-Report Version (AUDIT-C) were resourced from the Drink-less program, The University of Sydney.