Wong 2016.

Methods	RCT; parallel‐group (phase III). Single‐centre study
Participants	Chronic heart failure patients being managed in an outpatient setting. Patients had stable disease, but were judged to be iron deficient as per a serum ferritin < 100 mcg/L or < 300 mcg/L where TSAT was < 20%. Anaemic participants were not excluded, and so only data from non‐anaemic participants were extracted in association with the study authors.
Interventions	Single dose of intervention (ferric carboxymaltose, 1000 mg) or an equivalent volume of placebo (250 mL 0.9% sodium chloride)
Outcomes	Primary outcome was change in mean KCCQ score at 2 weeks post‐intervention. Secondary end points were 6MWT distance, PHQ‐9, grip strength, NT‐proBNP, Hb, ferritin and TSAT
Study funding arrangements	No information available on study funding arrangements
Author conflicts of interest	No information available on study funding arrangements
Sample size	24 non‐anaemic participants were randomised 1:1 to receive the intervention (n = 12) or control (n = 12) treatment
Notes	Study was retrospectively registered on a public trials register (ACTRN 12615000952549)
Risk of bias
Bias	Authors' judgement	Support for judgement
Random sequence generation (selection bias)	Low risk	Quote: "The allocation sequence was generated randomly by computer software performed at the clinical trials pharmacy. Randomization was stratified by NYHA class (I vs II + III)."
Allocation concealment (selection bias)	Low risk	Comment: no suggestion that using the technique described that allocation would have been known by the researchers ahead of time.
Blinding of participants and personnel (performance bias) All outcomes	Low risk	Quote: "Clinician was blinded as infusion was administered by a research nurse not involved in data collection/analysis. Subjects were blinded as infusion pump was set up behind a curtain to shield their view."
Blinding of outcome assessment (detection bias) All outcomes	Low risk	Quote: "Clinician was blinded as infusion was administered by a research nurse not involved in data collection/analysis. Subjects were blinded as infusion pump was set up behind a curtain to shield their view."
Incomplete outcome data (attrition bias) All outcomes	Low risk	Quote: "[single participant] refused to attend follow‐up on day 7 and refused to perform 6 minute walk test. Data from the walk test and data from day 7 were excluded from analysis." Comment: single participant lost to follow‐up and accounted for in analysis
Selective reporting (reporting bias)	High risk	Comment: despite data on haematinic markers and PHQ‐9 being collected, formal results were not available in the data provided by researchers. However, reference is made in the conference abstract notes to there being no difference between groups with respect to these metrics.
Other bias	Unclear risk	Comment: no pharmaceutical company involvement implied, but conference abstract lacks an explicit statement indicating independent study.