Oliveira 2015

Methods	Parallel RCT
Participants	Country of study: Brazil Setting: laboratory Condition: chronic temporomandibular disorder Prior management details: excluded if received any type of physiotherapy in preceding month n = 32 Age, mean (SD): active group 23.80 (7.3) years sham group 25.5 (6.3) years Duration of symptoms, months mean (SD): active group 29.8 (17.1), sham group 33.7 (22.8) Gender distribution: 3 M, 29 F
Interventions	Stimulation type: tDCS Stimulation parameters: intensity 2 mA, 35 cm2 electrodes, duration 20 min Stimulation location: anode M1 contralateral to painful side, cathode supraorbital area, contralateral to anode Number of treatments: daily sessions for 5 consecutive days. Then twice a week for 3 weeks, up to 10 sessions Control type: sham tDCS
Outcomes	Primary: pain VAS, anchors not reported When taken: 5 months postintervention, no data reported from formal study period Secondary: QoL WHO‐QoL, AEs
Notes	Sources of support: study was carried out without funding COI: study authors decare no COI
Risk of bias
Bias	Authors' judgement	Support for judgement
Random sequence generation (selection bias)	Low risk	Quote: “After the first comprehensive evaluation, the secretary of the clinical facility, who was not involved with any other procedures of the study, randomised participants who fulfilled the inclusion criteria for treatment and accepted to participate in the study. Randomisation occurred by the simple random method, in which each subject was invited to remove a small sealed envelope from a larger opaque envelope indicating two treatment groups.”
Allocation concealment (selection bias)	Low risk	Quote: “After the first comprehensive evaluation, the secretary of the clinical facility, who was not involved with any other procedures of the study, randomised participants who fulfilled the inclusion criteria for treatment and accepted to participate in the study."
Adequate blinding of participants?	Unclear risk	Comment: evidence that blinding can be inadequate at intensity of 2 mA. 15 guessed stimulation condition correctly in active group vs 7 in sham group
Adequate blinding of assessors?	Unclear risk	Comment: evidence that assessor blinding can be inadequate at intensity of 2 mA. No formal assessment of blinding success
Incomplete outcome data (attrition bias) All outcomes	Low risk	Comment: no attrition noted for core follow‐up points
Selective reporting (reporting bias)	Low risk	Comment: no numeric reporting of point estimates for most outcomes but data provided upon request
Study Size	High risk	Comment: n = 32
Study duration	Unclear risk	Comment: formal follow‐up for 3 weeks postintervention
Other bias	Low risk	Commet: no other bias detected