Allen 2011.

Methods	Randomised, placebo‐controlled trial
Participants	46 adult men and women with at least moderately severe RLS (IRLS >= 15), RLS symptoms at least five nights per week, and at least 15 PLMS/hour, enrolled from multiple sites
Interventions	Intervention: ferric carboxymaltose 500 mg in 100 mL normal saline, infused over 15 minutes, on days 0 and 5 Placebo: 100 mL normal saline with same dosing schedule
Outcomes	IRLS, RLS‐QoL, CGI‐I, PGI‐C, MOS scale, FSS, PLMS measured by actigraphy, ferritin
Notes	Funded by pharmaceutical company
Risk of bias
Bias	Authors' judgement	Support for judgement
Random sequence generation (selection bias)	Unclear risk	Study randomised, but method of sequence generation not specified
Allocation concealment (selection bias)	Low risk	Central allocation using interactive voice recognition system
Blinding (performance bias and detection bias) All outcomes	Low risk	Study nurse not blinded and interacted with participants, but was not an outcome assessor. IV bag and tubing concealed for study drug administration
Incomplete outcome data (attrition bias) All outcomes	Low risk	Three dropouts were not included in final analysis, all three from placebo group, all withdrew before receiving full dose of placebo (i.e. after 0 or 1 doses), none reported side effects
Selective reporting (reporting bias)	Unclear risk	Study protocol available but clinicaltrials.gov reports the protocol was first received 2/23/11, after the study was completed
Other bias	Low risk	No other risks identified