Study	Reason for exclusion
Bye 1982	The participants used supplemental oxygen at 60% and not from a cylinder supply, therefore they did not use ambulatory oxygen
Frank 2012	This study was neither randomised nor used a blinded design
Harris‐Eze 1994	The participants used supplemental oxygen at 60% and not from a cylinder supply, therefore they did not use ambulatory oxygen
Leach 1992	This study did not separately report ILD results and participants had resting hypoxia
Pouwels‐Fry 2008	This study was neither randomised nor used a blinded design
Schaeffer 2015	The participants used supplemental oxygen at 60% and not from a cylinder supply, therefore they did not use ambulatory oxygen
Tryfon 2003	The participants used supplemental oxygen at 60% and not from a cylinder supply, therefore they did not use ambulatory oxygen
Visca 2011	This study used an observational, retrospective design

Abbreviations: ILD: interstitial lung disease.