Minimal clinically important difference for the 6-min walk test: literature review and application to Morquio A syndrome

Table 1 Overview of studies that estimate the minimal clinically important difference (MCID) for the six-minute walk test (6MWT)

	Reference	Disease	N	Mean baseline 6MWT distance (m)	MCID determination method
					Anchor-based	Distribution-based
1 & 2	du Bois, 2010 [29] & du Bois, 2011 [30]	IPF	822	392	x	x
3	Swigris, 2010 [31]	IPF	154^a	373	x	x
4	Holland, 2009 [42]	Diffuse parenchymal lung disease	48^b	403	x	x
5	Holland, 2010 [43]	COPD	75	359	x	x
6	Polkey, 2013 [32]	COPD	2112	369	x
7	Puhan, 2008 [51]	COPD	460	361		x
8	Puhan, 2011 [44]	COPD	1218	348	x	x
9	Redelmeier, 1997 [45]	COPD	112	371	x
10	Wise, 2005 [52]	Emphysema (COPD)	470	353		x
11	Lee, 2014 [46]	Non-cystic fibrosis bronchiectasis	37	551	x	x
12 & 13	Gremeaux, 2011 [48] and [47]	CAD	81	NA	x	x
14	Gilbert, 2009 [53]	PAH	207	339–347		x
15	Mathai, 2012 [49]	PAH	405	343	x	x
16	Henricson, 2013 [28]	DMD	24	370	x
17	McDonald, 2013 [54]	DMD	174	358		x
18	Kwok, 2013 [50]	Frail elderly Asian persons	73	295	x	x
19	Taeger, 2013 [55]	CHF	NA	NA	NA	NA

CAD coronary artery disease, CHF chronic heart failure, COPD chronic obstructive pulmonary disease, DMD Duchenne muscular dystrophy, IPF idiopathic pulmonary fibrosis, MCID minimal clinically important difference, NA not available, PAH pulmonary arterial hypertension
^aOnly 123 patients had data at baseline and follow-up
^b24 patients had IPF

ISSN: 1750-1172