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Table 2 Patient characteristics (continuous variables)

From: Outcomes following large joint arthroplasty: does socio-economic status matter?

Characteristic Knee replacements (n = 1016) Hip replacements (n = 835)
Mean ± SD Mean ± SD
Age (years) 70.3 ± 8.6 68.4 ± 9.9
BMI (kg/m2) 32.4 ± 5.9 29.8 ± 5.7
SES score 6.3 ± 2.6 6.4 ± 2.7
Age-adjusted CCI* 1.8 ± 2.2 1.5 ± 2.1
Pre-op IKSSPain 5.4 ± 8.2 -
Post-op IKSSPain 35.2 ± 15.3 -
Change in IKSSPain 29.8 ± 16.4 -
Pre-op IKSSFunction ** 36.2 ± 19.5 -
Post-op IKSSFunction ** 58.5 ± 25.8 -
Change in IKSSFunction ** 22.3 ± 24.3 -
Pre-op PCS§ 27.1 ± 6.3 26.2 ± 5.5
Post-op PCS§ 37.8 ± 10.7 40.0 ± 11.1
Change in PCS§ 10.6 ± 10.9 13.8 ± 11.4
Pre-op MCS 48.7 ± 11.8 46.6 ± 12.0
Post-op MCS 50.9 ± 10.9 51.2 ± 10.8
Change in MCS 2.3 ± 12.5 4.6 ± 12.9
Pre-op HHSPain # - 12.0 ± 4.6
Post-op HHSPain # - 38.6 ± 9.0
Change in HHSPain # - 45.1 ± 17.5
Pre-op HHSFunction ¢ - 17.1 ± 9.1
Post-op HHSFunction ¢ - 34.2 ± 10.7
Change HHSFunction ¢ - 17.1 ± 10.9
  1. Abbreviations: BMI Body Masss Index, SES score Socioeconomic status score, CCI Charlson Comorbidity Index, pre-op pre-operative, post-op post-operative, IKSS Pain International Knee Society Pain Score, IKSS Function International Knee Society Function Score, PCS Short Form 12 Physical Component Score, MCS Short Form 12 Mental Component Score, HHS Pain Harris Hip Pain Score, HHS Function Harris Hip Function Score.
  2. BMI - Body Mass Index (weight [Kg]/height [m]2).
  3. SES score – Socioeconomic status score, (0 to 10) with a higher score representing socioeconomic advantage.
  4. *CCI – Charlson Comorbidity Index (0–43, age adjusted), with a higher score indicating a greater comorbidity burden.
  5. IKSSPain – International Knee Society Pain Score (0 to 50) with a higher score representing less pain.
  6. **IKSSFunction – International Knee Society Function Score (0 to 100) with a higher score representing better function.
  7. §PCS - score of ≥ 50 indicates no impairment; 40–49 mild impairment; 30–39 moderate impairment; and < 30 severe impairment.
  8. MCS - score of ≥ 50 indicates no distress; 40–49 mild distress; 30–39 moderate distress; and < 30 severe distress.
  9. #HHSPain – Harris Hip Pain Score (0 to 44) with a higher score representing less pain.
  10. ¢HHSFunction – Harris Hip Function Score (0 to 47) with a higher score representing better function.