Jensen 1991.

Methods	Design: randomised controlled trial Randomisation: individual Trial: daily oral iron versus placebo Date of study: not stated
Participants	Setting: Purdue University, Indiana, USA Malaria endemicity: not stated Included: women aged 18 years to 25 years (mean age 21 years) who were sedentary participants who did not regularly participate in an exercise programme. Willing to participate in an intensive 12‐week exercise programme Excluded: not stated Dropouts: not stated Sample size: total: 13; intervention: 7, control: 6
Interventions	Intervention: 50 mg elemental iron in the form of ferrous sulphate Control: placebo Duration: 12 weeks
Outcomes	Haemoglobin, iron status, exercise performance, fat mass, height, weight
Notes	Compliance: not stated Conflicts of interest: not stated Funded by: medication provided by SmithKline Consumer Products, Philadelphia, PA
Risk of bias
Bias	Authors' judgement	Support for judgement
Random sequence generation (selection bias)	Unclear risk	Not reported
Allocation concealment (selection bias)	Unclear risk	Not reported
Blinding of participants and personnel (performance bias) All outcomes	Low risk	Placebo administered
Blinding of outcome assessment (detection bias) All outcomes	Unclear risk	Not reported. Knowledge of allocation could influence outcome assessment regarding exercise performance
Incomplete outcome data (attrition bias) All outcomes	Low risk	No attrition reported
Selective reporting (reporting bias)	Low risk	Not reported
Other bias	Low risk	Not evident