Celnik 2008.

Methods	Randomized cross‐over trial
Participants	Methods of recruitment were not reported by authors 9 participants in a cross‐over design with 3 arms: 9 physical training group; 9 physical training and congruent action observation group; 9 physical training and incongruent action observation group Inclusion criteria: stroke patients with single unilateral cortical or subcortical lesions Exclusion criteria: there were no exclusion criteria described in the study Mean (SD) age: not reported by authors Stroke details: not reported by authors Stroke phase: chronic
Interventions	Physical training group performed voluntary thumb movements Physical training and congruent action observation group observed a video displaying thumb movements in the same direction to that physically practiced simultaneously Physical training and incongruent action observation group observed a video displaying thumb movements in a direction opposite to that physically practiced simultaneously Sessions were 30 minutes, 3 blocks of 10 minutes each separated by 2‐minute rest
Outcomes	Outcomes recorded before and after intervention Corticomotor excitability: MEP of agonist and antagonist muscles
Notes	‐
Risk of bias
Bias	Authors' judgement	Support for judgement
Random sequence generation (selection bias)	Low risk	Author's answer: "The allocation was generated randomly using Excel creating a random session order for each of the subjects and conditions."
Allocation concealment (selection bias)	Unclear risk	The author did not make clear whether there was allocation concealment
Blinding of participants and personnel (performance bias) All outcomes	Low risk	No blinding, but the outcome is not likely to be influenced by lack of blinding
Blinding of outcome assessment (detection bias) All outcomes	Low risk	Author's answer: "The outcome measures were analyzed by a blinded individual who did not participate in the data acquisition."
Incomplete outcome data (attrition bias) All outcomes	High risk	One participant could not complete the protocol due to TMS‐related headache. The reasons were provided, but the exclusion of 1/9 participants in a cross‐over design, with 3 arms, may have affected reliability of study results
Selective reporting (reporting bias)	Low risk	There is no trial registration, but the outcomes are significant, and there is no selective reporting within the study.
Other bias	Low risk