Carley 1985.

Methods	Design: 5‐week randomised controlled study
Participants	Health condition: elderly people with indolent pressure ulcers Sample size: Randomisation: at participant level (one ulcer per participant)§ Randomised (participants, n; ulcers, n): 30; 30 Experimental: 15; 15 Control: 15; 15 Analysed (participants, n; ulcers, n): 30; 30 Experimental: 15; 15 Control: 15; 15 Setting, country: Spaulding Rehabilitation Hospital (1 site), Boston, USA Inclusion criteria: inpatients pressure ulcer located either below the knee or over the sacral area Exclusion criteria: not reported Characteristics of pressure ulcer: Experimental Ulcer duration, mean (SD): 8.6 months (3.7) Ulcer location: below knee and/or over sacral region (number not reported) Ulcer stage: not reported Control Ulcer duration, mean (SD): 5.2 months (2.9) Ulcer location: below knee and/or over sacral region (number not reported) Ulcer stage: not reported Mean age (SD): Experimental: 70 years (18) Control: 74 years (14) Gender: Experimental: 53% male Control: 47% 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: LIDC plus cointervention Duration: 2 hours per session; 2 sessions per day (2 to 4 hours pause between 2 sessions); 5 days a week; total 5 weeks or until healed Electrode placement: one over the ulcer (active electrode) and the other 15‐20 cm away from the ulcer (dispersive electrode) Device, manufacturer: Portable Direct Current Stimulator, AGAR Israel Intensity of ES: not reported Frequency: not applicable (direct current) Type of current: direct Polarity: active electrode with negative polarity for first 3 days then dispersive electrode with negative polarity until the ulcer was healed or the healing plateaued the above protocol was restarted if healing plateaued Control: conventional wound therapy plus cointervention This included wet to dry gauge dressings, solution soaked dressings and few received whirlpool therapy for 5 times a week. Cointervention for both groups All ulcers were debrided before delivering any intervention.
Outcomes	Outcomes included in this review: presented as [name of outcome in review]‐ [name of outcome in study] Complications/adverse events‐ adverse events (expressed in descriptive format) Other outcomes not included in this review: (1) "area measurement" (i.e. volume) of the ulcer (expressed as cm3) Time point included in this review: week 5 (end of intervention) Other time points: baseline, week 1, week 2, week 3 and week 4
Notes	Withdrawals, (n; reason): Experimental: none Control: none Funding source: parts for experimental direct current generators and electronic support, AGAR, Kibbutz Ginosar, Israel electrode materials and supplies, KIM ED Industries Inc., New York, USA 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 to LIDC" p443 Comment: insufficient detail reported
Allocation concealment (selection bias)	Unclear risk	Comment: insufficient detail reported
Blinding of participants (performance bias) All outcomes	High risk	Quote: "Conventional wound therapy" p443 Comments: not possible to blind participants
Blinding of personnel (performance bias) All outcomes	High risk	Comments: not possible to blind personnel
Blinding of outcome assessment (detection bias) All outcomes	Unclear risk	Quote: "Area measurement of length, width, and depth to within the nearest millimetre were performed by the nursing staff and recorded without previous knowledge" p444 Comment: not clear if assessor was blinded
Incomplete outcome data (attrition bias) All outcomes	Low risk	Comment: no dropouts
Selective reporting (reporting bias)	Low risk	Comment: all pre stated outcomes were reported
Other bias	Unclear risk	Comment: trial was sponsored by third parties who were likely to have a vested interest in a positive finding