Table 2:

Six- Minute Walk Distance (6MWD) by study

Author year, location	Patient population	Follow-up (in months)	N at follow-up	Mean±SD or Median [IQR] 6MWD (m)	Predicted 6MWD (%)
Wright 2018, United Kingdom [31]	ICU	3	32I,27S	293 [124-444]I, 255 [120-337]S	NR
		6	28,25	374 [203-435], 321 [197-400]	NR
Wang 2017, China [32]	ARDS	12	24E	531±84	81±13
			48N	495±90	78±13
Viana 2017, Brazil [33]	ICU	3	20	273±126	NR
Dinglas 2016, United States [14]	ARDS	6	52	377± 145	65±24
		12	42	415 ± 154	71±23
Das Neves 2015, Argentina [34]	ICU	3	59	434± 181	63±22
		6	56	437 ± 166	116 ±176
		12	57	481 ± 143	93 ±117
Connolly 2015, United Kingdom [35]	ICU	3	30	362 ± 146.9	NR
Jones 2015, United Kingdom [15]	ICU	3	72	310±151	NR
Fan 2014, United States1 [12, 30]	ARDS	3	99	320±138	53±22
		6	117	338±128	57±21
		12	115	355±138	60±22
		24	112	371±151	63±25
		36	92	402±125	70 [58-82]
		48	98	401±123	70 [56-82]
		60	103	399±122	71 [59-83]
Needham 2014, United States2 [29, 36]	ARDS	6	158	368±139	64±22
		12	149	388±159	67±26
Denehy 2013, Australia3 [13, 16, 37, 38]	ICU	3	100	383±143	78.7±26.9
		6	89	398±161	72.5±27.4
		12	79	422±154	78.7±26.9
		48-60	48	508±118	70
Chiumello 2012, Italy [39]	ARDS	12	13	375 [335-445]	71a; 73b
			13	400 [350-450]
Elliott 2011, Australia4 [10, 40, 41]	ICU	2	155	400 ± 167
		7	145	435 ± 157
Herridge 2011, Canada5 [2, 28, 42, 43]	ARDS	3	80	281 [55-454]	49
		6	78	396 [244-250]	64
		12	81	422 [277-510]	66
		24	64	416 [285-496]	68
		36	65	418 [311-474]	67
		48	57	406 [314-488]	71
		60	54	436 [324-512]	76
Masclans 2011, Spain [44]	ARDS	6	38	368±69	60-65
Schandl 2011, Sweden [45]	ICU	3	52	512±144	NR
		6	42	533±150
		12	28	568±121
McWiliams 2009, United Kingdom [9]	ICU	2	38	424±111	NR

Abbreviations: ARDS, acute respiratory distress syndrome; ICU, intensive care unit; I, Intensive rehabilitation group; S, Standard rehabilitation group; E, ECMO group; N, non-ECMO group; 6MWD, six-minute walk distance; n, number; NR, not reported; SD, standard deviation; IQR, interquartile range; %, percentage.