Table 4

Standard multiple regression

Independent variablesUnstandardised coefficients B (SE)95% CIStandardised coefficients βSemipartial correlationsp Value
Postbronchodilator FEV1 (% predicted)−0.09 (0.03)−0.16 to −0.02−0.32−0.280.008
Sputum neutrophils AUC (%)0.12 (0.05)0.01 to 0.220.260.280.03
Disease duration (years)0.02 (0.04)−0.07 to 0.100.050.040.70
Modified JACS0.55 (0.69)−0.82 to 1.920.090.090.42
  • Dependent variable is RB1 %WA (n=91).

  • Model R2=0.27*, adjusted R2=0.23, R=0.52, p=0.001.

  • *Unique variance=0.16; shared variance=0.11.

  • Model equation: RB1 %WA =66.02–0.09 (postbronchodialator FEV1% predicted) +0.12 (sputum neutrophils AUC(%)).

  • Standard multiple regression using ‘enter’ method.

  • Unstandardised coefficients are used to construct a regression equation. Standardised coefficients are used to compare the unique contribution of each independent variable. Semipartial correlation coefficient squared indicates the contribution of the independent variable to the total R2.

  • AUC, area under the curve per unit time; FEV1, forced expiratory volume in 1 s; FVC, forced vital capacity; JACS, Juniper Asthma Control Score; RB1, right upper lobe apical segmental bronchus; WA, wall area.