Thorp 2001.

Methods	Study design: double blind crossover RCT Study duration: not reported Study follow‐up period: 13 weeks (6 weeks of treatment with first agent, 1 week washout period and 6 weeks of treatment with second agent)
Participants	Country: USA Setting: HD centre in Portland Veterans Affairs Medical centre, Portland, USA Health status: stable chronic adult HD patients with RLS diagnosed according to criteria similar to the current IRLSSG criteria Number: 16 Mean age ± SD: 64.1 ± 5.9 years Sex (M/F): 15/1 Exclusion criteria: participants with other cause of leg discomfort on neurological examination
Interventions	Treatment group Gabapentin 300 mg orally at the end of dialysis (3 times/wk) for 6 weeks Control group Placebo similar to gabapentin administered orally at the end of dialysis (3 times/wk) for 6 weeks Treatment administered under the direct supervision on nurse at the end of dialysis treatment. One week washout period between 2 treatments
Outcomes	RLS severity assessed by non‐validated Questionnaire at 0, 6, 13 weeks
Notes	Funding source: Drug was supplied by Pharmaceutical company
Risk of bias
Bias	Authors' judgement	Support for judgement
Random sequence generation (selection bias)	Unclear risk	No clear mention how randomised
Allocation concealment (selection bias)	Unclear risk	Method of concealment not reported
Blinding of participants and personnel (performance bias) All outcomes	Low risk	Patients, nurses, and physicians were blinded to treatment assignment
Blinding of outcome assessment (detection bias) All outcomes	Low risk	Assessments (questionnaires) were carried out while subjects and staff were still blinded to treatment
Incomplete outcome data (attrition bias) All outcomes	Low risk	Clearly mention drop outs and withdrawals with specified reasons
Selective reporting (reporting bias)	Unclear risk	No study protocol but expected outcome (improvement in severity of RLS) is clearly discussed
Other bias	High risk	"Gabapentin was supplied by Parke‐Davis Pharmaceuticals"