Table 3.

Corrected item-total correlations and internal consistency reliability if item was deleted for baseline scores of the interviewer and self-administered CRQ format

Item	CRQ-IA		CRQ-SA
	Corrected item-total correlation	Crohnbach alpha if item deleted	Corrected item-total correlation	Crohnbach alpha if item deleted
	Standardised dyspnoea domain		Standardised dyspnoea domain
1	0.46	0.70	0.56	0.74
2	0.68	0.62	0.67	0.71
3	0.50	0.69	0.44	0.78
4	0.32	0.74	0.70	0.71
5	0.56	0.66	0.48	0.77
	Fatigue domain		Fatigue domain
8	0.64	0.76	0.56	0.83
11	0.65	0.75	0.67	0.79
15	0.67	0.74	0.67	0.79
17	0.56	0.80	0.78	0.73
	Emotional function domain		Emotional function domain
6	0.66	0.71	0.80	0.85
9	-0.03	0.86	0.37	0.92
12	0.72	0.70	0.67	0.87
14	0.41	0.76	0.65	0.88
16	0.84	0.67	0.79	0.86
18	0.56	0.74	0.74	0.87
20	0.57	0.73	0.85	0.85
	Mastery domain		Mastery domain
7	0.49	0.75	0.67	0.83
10	0.65	0.66	0.76	0.80
13	0.44	0.78	0.65	0.85
19	0.72	0.63	0.77	0.79

CRQ-IA = Interviewer administered Chronic Respiratory Questionnaire CRQ-SA = Self-administered Chronic Respiratory Questionnaire