Reliability, validity and responsiveness of E-RS:COPD in patients with spirometric asthma-COPD overlap

Respiratory Research

Table 4 Construct validity: E-RS and wheeze Spearman correlations with SGRQ and clinical assessments

	Baseline week (Day − 7 to Day − 1)								Final treatment week (Day 21 to Day 28)
	SGRQ: Total	SGRQ: Activity	SGRQ: Impacts	SGRQ: Symptoms	Rescue medication use	Morning PEF	FEV₁	FEV₁% predicted	SGRQ: Total	SGRQ: Activity	SGRQ: Impacts	SGRQ: Symptoms	Rescue medication use	Morning PEF	FEV₁	FEV₁% predicted
N	326	328	329	327	336	338	338	338	321	324	325	325	326	327	327	327
RS-Total	0.46	0.43	0.36	0.39	0.33	−0.30	−0.18	−0.17	0.52	0.54	0.40	0.43	0.40	−0.27	− 0.18	− 0.17
RS-Cough and Sputum	0.32	0.29	0.22	0.35	0.26	−0.23	−0.11	− 0.11	0.38	0.36	0.29	0.44	0.34	− 0.16	− 0.11	− 0.10
RS-Chest Symptoms	0.37	0.32	0.3	0.33	0.29	− 0.19	−0.06	− 0.05	0.45	0.43	0.37	0.39	0.32	−0.18	− 0.09	− 0.08
RS-Breathlessness	0.48	0.48	0.38	0.35	0.33	−0.33	−0.24	− 0.22	0.53	0.59	0.42	0.38	0.40	−0.31	−0.23	− 0.23
Wheeze	0.38	0.33	0.29	0.41	0.33	−0.12	0.01	−0.11	0.42	0.38	0.34	0.43	0.32	−0.12	−0.04	− 0.06

Weak, moderate and strong correlations were defined as r ≤ 0.4 (unmarked), r > 0.4 (bold) and r > 0.7 (none present in this table), respectively
E-RS Evaluating Respiratory Symptoms in chronic obstructive pulmonary disease, FEV₁ forced expiratory volume in 1 s, PEF peak expiratory flow, RS respiratory symptoms, SGRQ St George’s Respiratory Questionnaire

ISSN: 1465-993X