Ahmed 2013.

Methods	Randomised open controlled trial. 1 hospital in Bangladesh.
Participants	Inclusion criteria: severe acute asthma. Exclusion criteria: none stated. 120 randomised. Intervention: 60 randomised. Control: 60 randomised.
Interventions	Intervention: salbutamol with MgSO₄. Control: salbutamol with normal saline.
Outcomes	PEF, respiratory rate, pulse rate, systolic, diastolic blood pressure, adverse effects.
Notes	Funding: not reported.
Risk of bias
Bias	Authors' judgement	Support for judgement
Random sequence generation (selection bias)	Unclear risk	No details but states randomized.
Allocation concealment (selection bias)	Unclear risk	No details given.
Blinding of participants and personnel (performance bias) All outcomes	High risk	Open‐label trial.
Blinding of outcome assessment (detection bias) All outcomes	High risk	Open‐label trial.
Incomplete outcome data (attrition bias) All outcomes	Unclear risk	Not clear how many participants completed the trial or if any were excluded from analysis.
Selective reporting (reporting bias)	Unclear risk	Conference abstract. no prospective trial registration identified, no outcome measures pre‐specified.