. 2017 Jun 7;7:2999. doi: 10.1038/s41598-017-02871-1

Table 1.

Multivariate regression results.

		% PRMⁱ	Local Sⁱ
fSAD	FEV₁ (% predicted)	—	<0.0001^d
	FEV₁/FVC	0.0114	0.0131^d
	SGRQ total score	—	0.0006
	6-min walk distance	0.0091	<0.0001
	MMRC dyspnea scale score^a	—	<0.0001
	BODE score^a	—	<0.0001
Emph	FEV₁ (% predicted)	—	<0.0001^b
	FEV₁/FVC	—	<0.0001
	SGRQ total score	<0.0001	—^d
	6-min walk distance	<0.0001	—^c,d
	MMRC dyspnea scale score^a	—	<0.0001
	BODE score^a	—	<0.0001

Note: Presented are the P values generated from stepwise regression models including the topological index S, respective PRM relative volume, age, gender, and body mass index (BMI). FEV₁ = forced expiratory volume in one second (% predicted); FVC = forced vital capacity; SGRQ = St. George’s Respiratory Questionnaire; MMRC = Modified Medical Research Council; BODE = body mass index, degree of airflow obstruction, dyspnea, and exercise capacity. ^adenotes use of a logistic instead of linear regression, ^bdenotes age was significant, ^cdenotes gender was significant, and ^ddenotes BMI was significant. Parameters not included in the model due to lack of significant effects are marked with a dash.