Table 3.

Univariate linear regression analysis

Variables	r	B with 95% CI	r 2	p	n
Height (cm)	−0.82	−61 (−90,−33)	0.67	0.001	13
DLCOc (mmol min−1 kPa−1)	−0.77	−1.9 (−3.2, −0.6)	0.60	0.009	10
RV/TLC (%)	0.74	0.57 (0.18, 0.97)	0.55	0.009	11
Age (years)	0.72	0.41 (0.15,0.68)	0.51	0.006	13

Analysis of the correlation of the AUC(CV > 20%) value with height, age and lung volumes related to closed airways and air trapping (RV/TLC) and ventilation/perfusion mismatch (DLCOc), respectively. Only lung function values obtained without bronchodilator of healthy subjects were used in the analysis. The results are listed in order of decreasing absolute value of the Pearson's correlation coefficient, r. B is the gradient of the regression line, given together with lower and upper boundary of the 95% confidence interval. The coefficient of determination, r², the associated significance value, p, and the number of healthy subjects, n, included in the calculations are also included.