Kang 2008a.

Methods	Method: randomised cross‐over trial Dropouts: none Adverse effects: none (Paik 2015 [pers comm]) Deaths: none ITT: yes, all participants completed the study
Participants	Country: Republic of Korea Sample size: 10 people with stroke aged 48 to 84 years Inclusion criteria: not explicitly stated; written informed consent Exclusion criteria: cerebellar or brainstem lesion; metallic body implant; pacemaker; cochlear implant; history of seizure; unstable medical condition; inability to perform outcome tasks; Na+ or Ca++ channel blockers
Interventions	Each participant underwent one of the following treatments A‐tDCS over the left DLPFC (2 mA for 20 minutes) followed by sham tDCS over the left DLPFC (2 mA for 1 minute), separated by at least 48 hours wash‐out period Sham tDCS over the left DLPFC (2 mA for 1 minute) followed by A‐tDCS over the left DLPFC (2 mA for 20 minutes), separated by at least 48 hours wash‐out period
Outcomes	Outcomes were measured at baseline, at the end of intervention period and at 3 hours postintervention Attention (Go/No‐Go test)
Notes
Risk of bias
Bias	Authors' judgement	Support for judgement
Random sequence generation (selection bias)	Unclear risk	Quote: "We applied random order using computerized program. Randominzation program is freely available in the Internet." (Paik 2015 [pers comm]) Comment: However, Patient‐ID and first session stimulation type were continuously alternated, as can be seen in Table 6
Allocation concealment (selection bias)	Unclear risk	Not described by the authors
Blinding of participants and personnel (performance bias) Subjective outcome measures	Low risk	There were no subjective outcome measures
Blinding of participants and personnel (performance bias) Objective outcome measures	Low risk	Participants were blinded; blinding of personnel not stated
Blinding of outcome assessment (detection bias) Subjective outcome measures	Low risk	There were no subjective outcome measures
Blinding of outcome assessment (detection bias) Objective outcome measures	Low risk	Outcome assessor was blinded; quote: "Both patients and the investigator that carried out the behavioral measurements were unaware of the type of intervention, because tDCS and sham were administered by another investigator who did not participate in the behavioral task or data analysis"
Incomplete outcome data (attrition bias) Subjective outcome measures	Low risk	There were no subjective outcome measures
Incomplete outcome data (attrition bias) Objective outcome measures	Low risk	All randomised participants apparently completed the study. No treatment withdrawals, no losses to follow‐up, no trial group changes and no major adverse events were stated
Selective reporting (reporting bias)	Unclear risk	All outcomes reported in the methods section reported. There was no published a priori trial protocol (Paik 2015 [pers comm])