Katsnelson 2004

Methods	Parallel RCT; 3 conditions
Participants	Country of study: Russia Setting: unclear Condition: hip and knee OA Prior management details: unclear n = 64 Age: unclear Duration of symptoms: unclear Gender distribution: unclear
Interventions	Stimulation type: CES Stimulation parameters: frequency not specified; pulse width not specified; intensity 11‐15 mA; waveform shape: condition 1 symmetric, condition 2 asymmetric; duration 40 min Stimulation location: appears to be 1 electrode attached to either mastoid process and 1 to the forehead Number of treatments: 5, x 1 daily for 5 consecutive Control type: sham unit ‐ visually indistinguishable from active units
Outcomes	Primary: 0‐10 NRS, anchors "no pain" to "very painful" When taken: unclear. Likely to be pre and post each stimulation session and then daily for 1 week after Secondary: none
Notes	AEs: not reported COI: no declaration made Sources of support: no declaration made
Risk of bias
Bias	Authors' judgement	Support for judgement
Random sequence generation (selection bias)	Unclear risk	Quote: "If subjects passed all criteria they were randomly assigned to one of the two active treatments or the sham treatment." Comment: method of randomisation not specified
Allocation concealment (selection bias)	Unclear risk	Comment: not specified
Adequate blinding of participants?	Low risk	Quote: "The physicians, like all other participants in the study, were unaware of which treatment each subject received."
Adequate blinding of assessors?	Low risk	Quote: "The physicians, like all other participants in the study, were unaware of which treatment each subject received."
Incomplete outcome data (attrition bias) All outcomes	Unclear risk	Comment: dropout level not specified
Selective reporting (reporting bias)	High risk	Comment: it is unclear in the report which time points were reported for primary outcomes
Study Size	High risk	Comment: < 50 participants per treatment arm
Study duration	High risk	Comment: < 2 weeks' follow‐up
Other bias	Unclear risk	Comment: the reporting of baseline group characteristics is insufficient