Jercinovic 1994.

Methods	Design: 4‐week randomised parallel controlled study
Participants	Health condition: people with spinal cord injury Sample size: Randomisation: at participant level (more than one ulcer for some participants)§ Randomised (participants, n; ulcers, n): 73; 109 Experimental: 42; 61 Control: 31; 48 Analysed (participants, n; ulcers, n): 73; 109 Experimental: 42; 61 Control: 31; 48 Setting, country: inpatient department (1 site), Slovenia Inclusion criteria: participants with spinal cord injury no known diagnosis of diabetes, vascular disease or cancer participants who had been disabled for more than 1 month pressure ulcer present below the level of spinal cord lesion prior treatment of pressure ulcer was only standard wound care Exclusion criteria: not reported Characteristics of pressure ulcer: Experimental Ulcer duration, mean (SD): 158 days (284) Ulcer location (n): sacrum (14), trochanter (16), legs (18); gluteal region (5), others (8) Ulcer stage: not reported Control Ulcer duration, mean (SD): 125 days (129) Ulcer location (n): sacrum (20), trochanter (11), legs (10), gluteal region (4), others (3) Ulcer stage: not reported Mean age (SD): Overall: 36 years (15) Experimental: not reported Control: not reported Gender: not reported §It is not clearly stated whether participants or pressure ulcers were randomised but the number of pressure ulcers is greater than the number of participants. We have assumed that randomisation was at the participant level.
Interventions	Total groups in this study: two Experimental: ES‐treated group plus conventional (standard) treatment Duration: 120 minutes per day; 5 days a week; Total 4 weeks. Electrode placement: both electrodes 3 centimetres away from the edge of the ulcer Device, manufacturer: Pals plus, Axelgaard Manufacturing, USA Intensity of ES: intensity was set to minimal visible muscle contraction Frequency: 40 Hz Type of current: pulsed Polarity: not reported Control: standard treatment Standard treatment for both groups Included debridement, standard dressing to the ulcer two or more times per day, as needed and a broad‐spectrum antibiotic in cases of infection
Outcomes	Outcomes included in this review: presented as [name of outcome in review] – [name of outcome in study] Rate of pressure ulcer healing ‐ healing rate (expressed as percentage per day) Other outcomes not included in this review: Wound depth Appearance of granulation Time point included in this review: week 4 (end of intervention) Other time points: baseline
Notes	Withdrawals, (n; reason): Experimental: none Control: none Funding source: this work was supported by the Ministry of Science and Technology of the Republic of Slovenia and the National Institute for Disability and Rehabilitation Research, Department of Education, Washington D.C., 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…" p226 Comment: insufficient detail reported
Allocation concealment (selection bias)	Unclear risk	Comment: insufficient detail reported
Blinding of participants (performance bias) All outcomes	High risk	Quote: "Because of visible muscle contractions, it was not possible to conduct a double‐blind clinical trial." p227 Comment: not possible to blind participants
Blinding of personnel (performance bias) All outcomes	High risk	Quote: "Because of visible muscle contractions, it was not possible to conduct a double‐blind clinical trial." p227 Comment: not possible to blind personnel
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
Selective reporting (reporting bias)	High risk	Quote: “To evaluate the healing process, weekly measurements of the wound area were performed. Changes in other very important ulcer measurements, such as the wound depth and the appearance of granulation, were recorded as well. Data obtained during the first four weeks of treatment were included in the data analysis for evaluation of treatment outcomes.” p227 Comment: all pre stated outcomes were not reported
Other bias	High risk	Comment: At the end of 4 weeks, the trial was continued for just some of those initially assigned to the control group. These patients were crossed over to the experimental group. However, only a small subgroup (20/40 pressure ulcers) Unit of randomisation was the participant but some participants had more than one pressure ulcer and data were analysed by pressure ulcers with no account for non‐independence of data Data analysed in many ways (e.g. exponential versus linear; different subgroups), not clear if this was done post hoc Trial sponsored by third parties who were likely to have a vested interest in a positive finding