Bale 1997.

Methods	A multicentre, prospective RCT with 61 participants Conducted in the UK Follow‐up: 30 d Participants recruited from 5 centres. Centres not specifically described
Participants	Inclusion criteria: aged ≥ 18 years, not pregnant, able to understand and consent to the trial, no history of poor compliance or previous involvement in the study, Stage II‐III PUs (using the Stirling classification) the largest wound diameter ≤ 11 cm with no sign of infection (identified as absence of bleeding, friable granulation tissue, offensive odour and pus secretion) Exclusion criteria: NR In the polyurethane foam dressing group at baseline (n = 29): median age (years): 74 gender:female (n = 17), male (n = 12) Stage II PU (n = 23), Stage III PU (n = 6) location of PUs: sacrum (n = 18), trochanter (n = 1), heel (n = 5), other/not specifically stated (n = 5) wound size (cm2): < 5 cm2 (n = 14); 5 cm2‐< 10 cm2 (n = 6); 10 cm2‐< 20 cm2 (n = 4); ≥ 20 cm2 (n = 5) amount of exudate: none (n = 8), slight (n = 9), moderate (n = 12) In the hydrocolloid dressing group at baseline (n = 31): median age (years): 73 gender: female (n = 16), male (n = 15) Stage of PU: Stage II (n = 22), Stage III (n = 9) location of PUs: sacrum (n = 13), trochanter (n = 1), heel (n = 11), other/not specifically stated (n = 6) wound size (cm2): < 5 cm2 (n = 10); 5 cm2‐< 10 cm2 (n = 6); 10 cm2‐< 20 cm2 (n = 9); ≥ 20 cm2 (n = 6) amount of exudate: none (n = 10), slight (n = 18), moderate (n = 3) The study received local research ethics committee approval at each centre and informed consent was obtained from all participants
Interventions	Group A: polyurethane foam dressing (Allevyn Adhesive) until the wound healed, or for a maximum of 30 d (n = 29) hydrocolloid dressing (Granuflex) until the wound healed, or for a maximum of 30 d (n = 31)
Outcomes	Primary outcomes: these outcomes are recorded as per the review in relation to primary and secondary Incidence of healed PUs (referred to as "healed wounds") Adverse events per participant Secondary outcomes: NR Economic outcomes: NR
Notes	Missing data/exclusions: of total number of participants recruited (n = 61); "Sixty patients were included in the statistical analysis. One patient was excluded who died shortly after the first dressing application (this was not dressing related)." (p. 464) High rate of participant dropout: 18 in the polyurethane foam group, 22 in the hydrocolloid group Wounds healed in 12 participants: 7 in the polyurethane foam dressing group, 5 in the hydrocolloid dressing group Adverse events: "There was only one dressing‐related adverse incident, where a patient treated with the polyurethane foam dressing developed a localised skin rash" (p. 464). Mention of "Damage to the surrounding skin, although rare, was reported in both groups…" (p. 466) Stirling classification system similar to NPUAP/EPUAP/PPPIA classification Study funded by Smith & Nephew, manufacturer of Allevyn Adhesive
Risk of bias
Bias	Authors' judgement	Support for judgement
Random sequence generation (selection bias)	Unclear risk	Quotation: "Patients allocated to one of two treatment groups sequentially for each centre, using an open randomisation list." Comment: unclear how random sequence was generated
Allocation concealment (selection bias)	Unclear risk	Quotation: "Patients allocated to one of two treatment groups sequentially for each centre, using an open randomisation list." Comment: not clear how allocation to group was concealed
Blinding of participants and personnel (performance bias) All outcomes	Unclear risk	No direct quotation addressing this aspect Comment: unclear whether participants and personnel were blinded to treatment group
Blinding of outcome assessment (detection bias) All outcomes	Unclear risk	No direct quotation addressing this aspect Comment: unclear, blinding of outcome assessment is not specifically stated
Incomplete outcome data (attrition bias) All outcomes	High risk	Quotations: "One patient was excluded who died shortly after the first dressing application (this was not dressing related)" “Forty of the 61 patients enrolled in the study were withdrawn. The main reasons for this were that the patients died or were discharged before their wounds healed." Comment: 67% of participants were withdrawn from the study
Selective reporting (reporting bias)	Low risk	No direct quotation addressing this aspect Comment: some data not reported, (e.g. the number of participants who required a dressing change due to discomfort)
Other bias	Low risk	No direct quotation addressing this aspect. Comment: none noted