| Methods |
Randomised, placebo controlled cross‐over study |
| Participants |
15 participants with CPEO or KSS due to single deletions of mtDNA |
| Interventions |
150 mg/kg of creatine monohydrate or placebo containing lactose for 6 weeks. 4‐week washout |
| Outcomes |
31P‐MRS (parameters included the PCr/ATP ratio at rest and the time constant for oxidative PCr |
| Notes |
No significant effect |
| Risk of bias |
| Bias |
Authors' judgement |
Support for judgement |
| Random sequence generation (selection bias) |
Low risk |
"Patients were individually randomized... using standard PC software." |
| Allocation concealment (selection bias) |
Low risk |
Allocation conducted by the central pharmacy |
| Incomplete outcome data (attrition bias)
All outcomes |
Low risk |
Incomplete outcome data adequately addressed |
| Selective reporting (reporting bias) |
Low risk |
All outcome measures in methods section were reported in results section |
| Other bias |
Low risk |
None identified |
| Blinding of participants and personnel (performance bias)
All outcomes |
Low risk |
In this double‐blind trial, creatine and placebo provided in "identical‐looking capsules." |
| Blinding of outcome assessment (detection bias)
All outcomes |
Low risk |
Participants were randomly assigned to start in either the creatine or placebo arm. "Evaluations and calculations on efficacy measures were performed blinded." |
