Benes 1999.

Methods	Randomised controlled crossover trial of levodopa versus placebo Dropouts/withdrawals: PP of 32 with premature discontinuations of 3 patients in the treatment group.
Participants	Included/analysed: 35/32 Demographics: 13 male, age 56 years Diagnosis: RLS according to IRLSSG, PLMS/h > 5, symptoms for at least 2 weeks, sleep onset latency > 30 min and/or sleep efficiency ≤ 85% Setting: 3 centres in Germany Baseline: PLMI (using actigraphy) 49.5 ± 29.2
Interventions	Intervention: flexible uptitration of single dose levodopa/benserazide from 100 mg/25 mg to 200 mg/50 mg in 3 weeks, maintenance for 1 week Control: flexible uptitration of single dose placebo capsules in 3 weeks, maintenance for 1 week No washout between treatment periods
Outcomes	Change of symptoms: CGI‐Improvement Objective quality of sleep: PLM‐Index (using actigraphy) Self rated quality of sleep: SF‐A Quality of life: VAS on life satisfaction Safety: Number of drop outs due to adverse events, number of patients experiencing adverse events
funding source	The study was supported by a grant from Hoffmann La‐Roche, Inc.
Notes	PLMI: index of number of periodic limb movements per hour time in bed; CGI‐I: Clinical Gobla Impressions ‐ Improvement; SF‐A: Schlaffragebogen‐A; VAS: Visual Analogue Scale
Risk of bias
Bias	Authors' judgement	Support for judgement
Adequate sequence generation?	Low risk	Randomisation list was produced by the statistical department of the sponsor.
Allocation concealment?	Low risk	Patients had to be allocated to a numbered medication in ascending order. Due to the blinding of the medication, investigators and patients were not informed regarding treatment sequence or medication.
Blinding? All outcomes	Unclear risk	White capsules of identical size and shape, the capsules were not differentiable. The capsules which had to be taken in one cross‐over period were filled in a glass and labelled with "week 3‐6" and "week 7‐10", respectively. Blinding of polysomnography raters was not mentioned.
Incomplete outcome data addressed? All outcomes	Low risk	No incomplete outcome data.
Free of selective reporting?	Low risk	All results reported as prespecified with additional sleep data.
Free of other bias?	Low risk	Low indication of bias.