Table 7– Estimates of minimally important differences (MIDs) for Capacity of Daily Living during the Morning (CDLM) and Global Chest Symptoms Questionnaire (GCSQ) scores using anchor- and distribution-based approaches

	Subjects n	Anchor-based approach	Distribution-based approaches
	Subjects n	SGRQ-C (sem)^#	SEM^¶	0.5 sd⁺
CDLM questonnaire
Study 1	469	0.15 (0.01)	0.19	0.40
Study 2	316	0.22 (0.02)	0.28	0.42
GCSQ
Study 1	578	0.13 (0.01)	0.27	0.32
Study 2	418	0.12 (0.02)	0.22	0.44

SGRQ-C: St George's Respiratory Questionnaire for chronic obstructive pulmonary disease patients; SEM: standard error of measurement. ^#: MID = 4; ^¶: MID = sd×square root (1–α); ⁺: MID = 0.5×sd.