Study	Reason for exclusion
Ashby 2012	Although the study was an RCT, it had a mixed‐dressing control arm with foam dressings being 1 of 3 dressing options based on health professional and participant choice rather than randomisation
Avanzi 2000	Paper incomplete and review authors unable to access it
Banks 1994b	PU classification system not stated. Review authors unable to access original data
Banks 1994c	PU classification system not stated. Review authors unable to access original data
Banks 1997	PU classification system not stated. Review authors unable to access original data
Brown‐Etris 1996	The intervention dressing (Transorbant) has dry hydrogel and foam layers. We excluded this study as the hydrogel layer was closest to the skin, and the foam was an outer layer that provided cushioning
Diehm 2005	Not a RCT or cluster‐RCT
Münter 2006	No subgroup analysis of participants with PUs. Review authors unable to access original data
Oleske 1986	Not a RCT or cluster‐RCT
Palao i Domenech 2008	No subgroup analysis of participants with PUs. Unable to contact study authors
Parish 2008	Not a RCT or cluster‐RCT
Piatkowski 2012	Administered foam dressing to participants on both trial arms
Reynolds 2004	PU classification system not stated. Unable to contact study author
Romanelli 2009	Subanalysis of larger study by Palao i Domenech 2008. Does not include participants with PUs
Wagstaff 2014	While this trial compared two foams for the treatment of PUs, their application occurred as a component of negative pressure wound therapy following surgical debridement rather than as a wound dressing
Zimny 2003	Participants had neuropathic foot ulcers, not PUs.

PU: pressure ulcer; RCT: randomised controlled trial