Karba 1995.

Methods	Design: parallel randomised controlled study
Participants	Health condition: people with spinal cord injury Sample size: Randomisation: at participant level (one ulcer per participant)§ Randomised (participants, n; ulcers, n): 12; 12 Experimental: 6; 6 Control: 6; 6 Analysed (participants, n; ulcers, n): 12; 12 Experimental: 6; 6 Control: 6; 6 Setting, country: inpatient department (1 site), Slovenia Inclusion criteria: male participants with spinal cord injury who had developed a pressure ulcer Exclusion criteria: not reported Characteristics of pressure ulcer: Experimental Ulcer duration: not reported Ulcer location: not reported Ulcer stage: not reported Control Ulcer duration: not reported Ulcer location: not reported Ulcer stage: not reported Age (range): Overall: 29 to 42 years Experimental: not reported Control: not reported Gender: Overall: 100% male §It is not clearly stated whether participants or pressure ulcers were randomised but the number of pressure ulcers equals the number of participants.
Interventions	Total groups in this study: two Experimental: ES group and standard care Duration: 120 minutes per day; until healed Electrode placement: healthy skin at ulcer edge Device, manufacturer: Encore Tm Plus, Axelgaard Manufacturing, Ltd. USA Intensity of ES: visible contraction of the muscles in the wound area Frequency: not reported Type of current: pulsed Polarity: not reported Control: CO group Sham with no ES delivered Standard care for both groups Cleaning with a physiological solution and covering with semi‐occlusive foam gel dressings. The dressings were changed as necessary or at the latest after one week.
Outcomes	Outcomes included in this review: presented as [name of outcome in review]‐ [name of outcome in study] Surface area of pressure ulcers ‐ wound area (expressed as mm2)* Rate of pressure ulcer healing ‐ relative healing rate (expressed as percentage per day) Time point included in this review: until healed† Other time points: baseline *converted to cm2 for the purpose of analyses †data were captured at varying time points (between 10 and 56 days); we extracted the data for 2 weeks before participants in the control group were crossed to experimental group
Notes	Withdrawals, (n; reason): Experimental: none Control: none Funding source: this study was supported by: Ministry of Science and Technology of the Republic of Slovenia Johnson & Johnson S.E. Inc., Ljubljana, Slovenia for providing the wound dressings Trial registration or published protocol: no information about trial registration or published protocol provided
Risk of bias
Bias	Authors' judgement	Support for judgement
Random sequence generation (selection bias)	Unclear risk	Quote: "randomly assigned" p671 Comment: insufficient detail reported
Allocation concealment (selection bias)	Unclear risk	Comment: insufficient detail reported
Blinding of participants (performance bias) All outcomes	Low risk	Quote: control participants received "sham treatment". p671
Blinding of personnel (performance bias) All outcomes	Unclear risk	Comment: insufficient detail reported
Blinding of outcome assessment (detection bias) All outcomes	Unclear risk	Comment: insufficient detail reported
Incomplete outcome data (attrition bias) All outcomes	Low risk	Comment: no dropouts. All data are available in Table 2
Selective reporting (reporting bias)	Low risk	Comment: all pre stated outcomes were reported
Other bias	High risk	Comment: Participants in the control group were crossed to experimental group at varying time points (between 10 and 56 days) Trial was sponsored by third parties who were likely to have a vested interest in a positive finding