| Methods |
RCT; parallel‐group (phase III). Undertaken in 3 centres in Sweden |
| Participants |
Patients aged 18‐70 years with restless legs syndrome and iron deficiency. Iron deficiency originally defined as serum ferritin < 30 mcg/L. Later revised to < 45 mcg/L. Hb was not considered as part of study inclusion criteria, but mean Hb at start of study was > 120 g/L. |
| Interventions |
5 doses of 200 mg iron sucrose (1000 mg total) evenly spread over 2 weeks |
| Outcomes |
Primary outcome measure was IRLS score at end of follow‐up (week 11). Hb and ferritin data were also collected. Adverse event data were collected. |
| Study funding arrangements |
Study supported by Renapharma Pty Ltd, Uppsala, Sweden |
| Author conflicts of interest |
Authors deny any conflicts of interest |
| Sample size |
86 participants were randomised to receive the intervention (n = 43) or the control (n = 43) treatment. |
| Notes |
Study registered in a public trials register (ISRCTN 82469428). |
| Risk of bias |
| Bias |
Authors' judgement |
Support for judgement |
| Random sequence generation (selection bias) |
Low risk |
Comment: no specific reference to type of sequence generation used, but stated to be "random and consecutive". |
| Allocation concealment (selection bias) |
Unclear risk |
Comment: no clear statement on allocation concealment, and lack of information on sequence generation precludes a "low‐risk" judgement. |
| Blinding of participants and personnel (performance bias)
All outcomes |
Low risk |
Quote: "Specific logistics were implemented to keep the study blinded to both patients and study personnel. Infusions were prepared by the local pharmacy, infusion bags and disposables were non‐transparent. Infusions and blood chemistry results were supervised by personnel otherwise not involved in the care of the patient." |
| Blinding of outcome assessment (detection bias)
All outcomes |
Low risk |
Quote: "Specific logistics were implemented to keep the study blinded to both patients and study personnel. Infusions were prepared by the local pharmacy, infusion bags and disposables were non‐transparent. Infusions and blood chemistry results were supervised by personnel otherwise not involved in the care of the patient." |
| Incomplete outcome data (attrition bias)
All outcomes |
Low risk |
Comment: all participant exclusions were accounted for. An ITT analysis was performed. |
| Selective reporting (reporting bias) |
Low risk |
Comment: all stated outcomes were reported consistently through to end of follow‐up. |
| Other bias |
Unclear risk |
Comment: unspecified funding was received from Renapharma Pty. Ltd. |
