Long-term variability of impulse oscillometry and spirometry in stable COPD and asthma

Respiratory Research

Table 4 Multiple regression analyses to determine long-term variability and airflow obstruction

	B	SE	β-Coefficient	t	P value
Predictors of long-term variability of log R5
%FEV1	0.007	0.003	0.347	2.899	0.005
Mean R5	0.059	0.020	0.344	2.914	0.005
Age	− 0.003	0.004	− 0.075	− 0.650	0.518
BMI	− 0.005	0.010	− 0.056	− 0.498	0.620
Predictors of long-term variability of log R20
%FEV1	0.000	0.002	− 0.006	− 0.051	0.959
Mean R20	0.118	0.037	0.357	3.158	0.002
Age	0.001	0.003	0.053	0.478	0.634
BMI	0.012	0.008	0.168	1.476	0.144
Predictors of long-term variability of log R5-R20
%FEV1	0.007	0.003	0.303	2.441	0.017
Mean R5-20	0.108	0.031	0.437	3.509	0.001
Age	0.002	0.004	0.057	0.500	0.618
BMI	− 0.013	0.010	− 0.144	− 1.304	0.196

Multiple regression analysis was performed using SPSS 22.0. See Table 1 and Table 2 legend for expansion of abbreviations

ISSN: 1465-993X