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Table 2 Descriptive statistics. Patient characteristics, assessed pre-operatively

From: Patient and surgical prognostic factors for inpatient functional recovery following THA and TKA: a prospective cohort study

Patient characteristic Total cohort, N = 354 TKA, n = 238 (67.2%) THA, n = 116 (32.8%) p value
Age (years), mean (SD) 68.9 (9.2) 69.5 (8.9) 67.7 (9.9) 0.09
Sex, N (%)     0.30
 Female 185(52.0%) 129 (54.2%) 56 (48.3%)
 Male 169 (48.0%) 109 (45.8%) 60 (51.7%)
BMI (kg/m2)
 Median (IQR) 30.0 (26.6, 33.6) 30.3 (27.0, 34.5) 28.4 (26.1, 31.3) 0.002*
 Range (18.1–48.8)
Missing: n = 1 (0.3%)
(18.1–48.8) (18.9–45.8)
ASA grade, N (%)
 1 27 (8.2%) 12 (5.5%) 15 (13.5%) < 0.001*
 2 180 (54.4%) 111 (50.5%) 69 (62.2%)
 3 122 (36.9%) 97 (44.1%) 25 (22.5%)
 4 2 (0.6%) 0 (0%) 2 (1.8%)
 Median (IQR) 2 (2, 3)
Missing: n = 23 (6.5%)
2 (2, 3) 2 (2, 2)
Pre-operative Hb (g/L)
 Mean (SD) 137.9 (11.8)
Missing: n = 4 (1.1%)
137.5 (11.6) 138.7 (12.1) 0.40
Pre-operative pain (VAS 0–100)     0.05
 Mean (SD) 38.9 (26.3)
Missing: n = 6 (1.7%)
37.0 (26.7) 42.8 (25.0)
Pre-operative function
OKS/OHS (0–48)
  Mean (SD) 25.5 (8.0)
Missing: n = 2 (0.6%)
26.0 (8.0) 23.7 (7.9) 0.02*
EQ-5D VAS (0–100)
  Median (IQR) 80 (70, 90) 80 (70, 90) 80 (65, 90) 0.11
  Range (10–100)
Missing: n = 4 (1.1%)
(10–100) (18–100)
mILAS (0-36)
  Median (IQR) 0 (0.0, 0.0) 0 (0.0, 0.0) 0 (0.0, 0.0) 0.16
  Range (0–11) (0–11) (0–11)
TUG (s)
  Median (IQR) 8.79 (7.41, 11.09) 8.76 (7.58, 11.05) 8.98 (7.17, 11.28) 0.56
  Range (4.39–30.93) (4.97–29.29) (4.39–30.93)
10mWT (s)
  Median (IQR) 7.61 (6.49, 9.40) 7.65 (6.52, 9.40) 7.58 (6.44, 9.42) 0.71
  Range (4.23–27.02) (4.23–22.94) (4.75–27.02)
RAPT score
  Mean (SD) 9.48 (2.1)
Missing: n = 5 (1.4%)
9.3 (2.2) 9.8 (2.0) 0.03*
  1. Missing data: was omitted during pre-admission assessment or could not be extracted from patient medical chart
  2. ASA American Society of Anaesthesiologists, BMI body mass index, EQ-5D VAS EuroQol-5 Dimension Visual Analogue Scale, Hb haemaglobin, IQR inter-quartile range, mILAS modified Iowa Level of Assistance Scale, OKS Oxford Knee Score, OHS Oxford Hip Score, RAPT Risk Assessment and Prediction Tool, THA total hip arthroplasty, TKA total knee arthroplasty, TUG Timed Up and Go test, VAS visual analogue scale, 10mWT ten-metre walk test
  3. *Statistical significance assessed at the 0.05 level. p values were derived from an independent-samples t-test, Mann-Whitney U test, or chi-square test comparing TKA and THA cohorts, as appropriate for variable type