Internal consistency reliability is a poor predictor of responsiveness

Table 1 Internal consistency reliability and responsiveness. Studies 1 and 2

Study	Instrument and domain	Internal consistency reliability^¶	Standardised response mean^#
Study 1	CRQ-IA
	Dyspnea individualised	0.78	1.16
	Dyspnea standardised	0.82	0.81
	Fatigue	0.86	0.85
	Emotional function	0.88	0.76
	Mastery	0.75	0.95
	SGRQ
	Symptoms	0.63	0.27
	Activities	0.75	0.49
	Impact	0.73	0.69
	Total	0.84	0.66
	SF-36
	Physical Functioning	0.80	0.83
	Role Physical	0.77	0.54
	Bodily Pain	0.93	0.29
	General Health	0.64	0.13
	Vitality	0.80	0.65
	Social Functioning	0.74	0.63
	Role Emotional	0.84	0.50
	Mental Health	0.84	0.41
Study 2	CRQ-IA
	Dyspnea individualised	0.77	0.66
	Dyspnea standardised	0.86	0.50
	Fatigue	0.80	0.25
	Emotional function	0.90	0.24
	Mastery	0.92	0.38
	CRQ-SA
	Dyspnea individualised	0.83	0.84
	Dyspnea standardised	0.86	0.69
	Fatigue	0.84	0.60
	Emotional function	0.89	0.56
	Mastery	0.87	0.70
	SGRQ
	Symptoms	0.72	0.34
	Activities	0.81	0.33
	Impact	0.80	0.46
	Total	0.88	0.51
	SF-36
	Physical Functioning	0.87	0.31
	Role Physical	0.91	0.19
	Bodily Pain	0.83	0.22
	General Health	0.76	0.22
	Vitality	0.86	0.32
	Social Functioning	0.90	0.21
	Role Emotional	0.92	0.07
	Mental Health	0.87	0.15

¶Cronbach's alpha; # Change score (follow-up minus baseline) / standard deviation of change score; * Pearson correlation coefficient; CRQ-IA interviewer-administered CRQ; CRQ-SA self-administered CRQ

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