Garland 2007.

Methods	Randomised multicentre controlled trial 2‐arm parallel group design Number of participating centres: 3 Trial duration: 12 weeks Randomisation stratified according to study site No power calculation reported
Participants	100 patients randomised 58 patients with knee OA reported at baseline; 41 out of 58 candidates for total knee arthroplasty Study joints: 58 knees Number of females: 38 of 58 (66%) Average age: 66 Disease duration: 8.4 years
Interventions	Experimental intervention: pulsed electrical stimulation Control intervention: sham intervention Duration of treatment period: 12 weeks Analgesics allowed and intake assessed, but unclear whether intake was similar. Device: BIO‐1000 Self‐administered: yes Waveform: unclear Pulse width: unclear Pulse frequency: 100 Hz Amplitude: below sensory threshold, initial increase of amplitude up to 12 Volt until a tingling sensation was felt then reduction of the amplitude until this sensation disappeared  Duration of stimulation per session: 8.2 hours in active group, 7.8 hours in sham group (mean daily application time) Electrodes: flexible electrodes embedded in garment, type not reported Electrode placement: negative electrode at patella, positive over anterior distal thigh
Outcomes	Extracted pain outcome: global pain after 12 weeks, described as "Considering your pain and symptoms in your study joint how are you doing today? (VAS)" Extracted function outcome: WOMAC disability subscore after 12 weeks (VAS) No primary outcome reported
Notes	*Due to major protocol violations, all 42 randomised patient of one site were excluded by Garland et al
Risk of bias
Bias	Authors' judgement	Support for judgement
Adequate sequence generation?	Low risk	Random number table
Allocation concealment?	Low risk	Central randomisation
Free of selective reporting?	Unclear risk	Quote: "Total WOMAC scores were not a defined outcome in the protocol, but are shown in Tables II(a)‐(d)."
Adequate blinding of patients?	Low risk	Use of sham device: BIO‐1000, indistinguishable from active device, with automatic shut‐off as soon as amplitude is reduced (all patients were instructed to reduce intensity just below perception level). Further adjustments required all devices to be restarted.
Incomplete outcome reporting: intention‐to‐treat analysis performed? Pain	High risk	Due to major protocol violations, all 42 randomised patient of 1 site were excluded by original authors. From the other site, all patients randomised were included in the analysis.
Incomplete outcome reporting: intention‐to‐treat analysis performed? Function	High risk	See above
Funding by commercial organisation avoided?	High risk	Sponsor: BioniCare Medical Technologies
Funding by non‐profit organisation?	Unclear risk	No information provided