Münter 2006.

Methods	Randomised controlled trial. Multi‐centre—80 study centres, 9 countries (Belgium, Brazil, Canada, Denmark, Germany, Italy, Slovenia, Switzerland, UK). From an interim analysis, a sample of 272 participants per treatment group was estimated as required to detect a difference in means of 17.1 relative surface area with standard deviation 71.0, at 80% power and 5% significance level. To ensure adequate recruitment, while allowing for a withdrawal rate of 15%, a target of "over 600" was set
Participants	619 participants with chronic wounds exhibiting delayed healing and producing moderate to high levels of exudate were recruited. Ulcers had to be < 0.5 cm in depth and characterised by at least one of the following: delayed healing due to bacteria (< 0.5 cm ulcer reduction or no change or increase in wound volume or surface area over past 4 weeks); being at risk of infection (such as diabetic wounds or sacral pressure ulcers); discolouration of granulation tissue; malodour; or clinical infection requiring treatment with systemic antibiotics Group 1: 293 participants Group 2: 326 participants Breakdown of proportions of participants according to wound type: Group 1: venous leg ulcers 50%; mixed venous/arterial leg ulcers 17%; pressure ulcers 7%; diabetic foot ulcers 8%; other wounds 18% Group 2: venous leg ulcers 46%; mixed venous/arterial leg ulcers 21%; pressure ulcers 8%; diabetic foot ulcers 8%; other wounds 17% Numbers of participants with leg ulcers, with breakdown according to aetiology: Group 1: 197—venous 147/197 (75%); venous/arterial 50/197 (25%) Group 2: 218—venous 150/218 (69%); venous/arterial 68/218 (31%) Mean baseline ulcer size in cm2 ± SD (median, range) for all wound types (separate data not presented for participants with leg ulcers): Group 1: 36.6 ± 64.4 (12.0, 0.1 to 400) Group 2: 52.9 ± 90.0 (20.0, 0.1 to 700) No data on baseline wound duration were provided Participants with clinically infected wounds, or wounds deemed at risk of infection, were eligible for inclusion, but no data related to prevalence of infection at baseline were presented
Interventions	Group 1: local best practice, including the following dressings—foams/alginates (53%), hydrocolloids (12%), gauze (3%), silver dressings (17%), other antimicrobial dressings (9%), other active dressings (6%) Group 2: silver‐donating foam dressing (Contreet Ag). Both adhesive and non‐adhesive versions of the dressing were used Wound management for all participants (including compression therapy) was performed in line with local protocols, guidelines and dressing manufacturers’ instructions. All dressings were changed between weekly assessments when judged necessary by the wound care practitioners Duration of treatment was 4 weeks
Outcomes	Primary outcomes: Median percentage change in ulcer area at 4 weeks for venous and venous/arterial leg ulcer participants: Group 1: ‐28.8 (n = 197) Group 2: ‐45.5 (n = 218) The trial authors reported that the between‐group difference was statistically significant (P value 0.0001) Median percentage change in ulcer area at 4 weeks for venous leg ulcer participants: Group 1: ‐26.9 (n = 147) Group 2: ‐46.2 (n = 150) The trial authors reported that the between‐group difference was statistically significant (P value 0.0001) Secondary outcomes: Numbers (%) of participants with pain at dressing change for venous and venous/arterial leg ulcers: Group 1: 2/197 (1%) Group 2: 1/218 (< 1%) The trial authors reported that the between‐group difference was statistically significant (P value < 0.0001) Numbers (%) of participants with ulcer pain between dressing changes for venous and venous/arterial leg ulcers: Group 1: 2/197 (1%) Group 2: 1/218 (< 1%) The trial authors reported that the between‐group difference was statistically significant (P value 0.0003) Adverse events—numbers (%) of participants with macerated peri‐ulcer skin at 4 weeks for venous and venous/arterial leg ulcer participants: Group 1: 27/197 (13.7%) (22.1% at baseline) Group 2. 26/218 (12.0%) (28.6% at baseline) The trial authors reported that the between‐group difference at week 4 was not statistically significant, but no P value was provided Health‐related quality of life (EQ‐5D) for venous leg ulcer participants: The trial authors reported that the between‐group difference for the overall EQ‐5D score at 4 weeks was not statistically significant, but no data were provided apart from the P value (P value 0.0878) When analysed separately, significantly less pain/discomfort was reported in Group 2 compared with Group 1; again, no data shown other than the P value (P value 0.0426). Not stated whether values were adjusted for baseline scores (and no baseline scores were presented) Cost‐effectiveness parameters—mean wear time of dressing for venous and venous/arterial leg ulcer participants: Group 1: 2.1 days Group 2: 3.5 days The trial authors reported that the between‐group difference was statistically significant (P value < 0.0001)
Notes	No outcome data on infection‐related or microbiological outcomes were presented No information about withdrawals was provided Note: 17% of participants in the control group received silver dressings
Risk of bias
Bias	Authors' judgement	Support for judgement
Random sequence generation (selection bias)	Low risk	Quote: "Using a computer‐generated list in sealed envelopes, patients were randomly assigned to a four‐week treatment period of either silver foam or LBP" Comment: The above information suggested a satisfactory method of random sequence generation
Allocation concealment (selection bias)	Unclear risk	Quote: "Using a computer‐generated list in sealed envelopes, patients were randomly assigned to a four‐week treatment period of either silver foam or LBP" Comment: No statement was made as to whether envelopes were opaque
Blinding (performance bias and detection bias) Participant blinded to the intervention	Unclear risk	Comment: The trial was described as "open", and no mention was made of participant blinding
Blinding (performance bias and detection bias) Outcome assessor blinded to the intervention	Unclear risk	Quote: "The study personnel at the participating centres completed the data collection forms" Comment: The trial was described as "open", and no mention was made of outcome assessor blinding
Incomplete outcome data (attrition bias) Drop out rate described	Low risk	Comment: Although no explicit statement is made, tabulated outcome data for leg ulcers indicate that analyses were based on all participants
Incomplete outcome data (attrition bias) Drop out rate acceptable	Low risk	Comment: Although no explicit statement is made, tabulated outcome data for leg ulcers indicate that analyses were based on all participants
Incomplete outcome data (attrition bias) ITT analysis	Low risk	Quote: "Data were analysed on the principle of last observation carried forward" Quote: "The obtained data were analysed as intention to treat (ITT)" Comment: Although no explicit statement is made, tabulated outcome data for leg ulcers indicate that analyses were based on all participants
Baseline factors comparable	Unclear risk	Baseline ulcer size was reported for all wound types together, not separately for the leg ulcer participants. For the overall group, the baseline ulcer size was larger in Group 2. No information on baseline ulcer duration was provided