Table 3

Final multiple linear regression models of the association between four determinants of functioning and maximal aerobic capacity and potential confounders

ModelβUnst. β95% CIP valueR2
Lifting capacity (kg)
7.83(−1.31 to 16.98)0.0920.35
 V̇O2max (L/min)0.325.24(1.57 to 8.90)0.006
 Sex*−0.37−6.93(−11.16 to −2.70)0.002
Work ability
4.50(0.93 to 8.06)0.0140.38
 V̇O2max (L/min)0.120.49(−0.43 to 1.41)0.288
 Educational level0.331.42(0.45 to 2.39)0.005
 Distress (BSI-GSIT)−0.33−0.09(−0.14 to −0.03)0.003
 Diagnosis area: generalised back−0.06−0.31(−1.58 to 0.97)0.629
 Diagnosis area: back and legs−0.42−2.85(−4.46 to −1.23)0.001
 Diagnosis area: multiple sites−0.29−1.61(-2.97 to −0.25)0.021
Pain-related disability
29.93(18.19 to 41.67)0.0000.18
 V̇O2max (l/min)−0.08−1.75(−6.36 to 2.86)0.452
 Pain intensity (VAS)0.402.18(0.99 to 3.37)0.001
Physical functioning
 (Constant)89.99(59.85 to 120.14)0.0000.23
 V̇O2max (L/min)0.092.95(−4.37 to 10.26)0.425
 Pain intensity (VAS)−0.34−2.97(−4.84 to −1.11)0.002
 BMI (kg/m2)−0.30−1.10(−1.88 to −0.32)0.006
  • *0=male, 1=female.

  • †Reference category: low back.

  • BMI, body mass index; BSI, Brief Symptom Inventory; GSIT, Global Severity Index Total Score; VAS, Visual Analogue Scale; V̇O2max, maximal aerobic capacity.