Modaresi 2015.

Study characteristics
Methods	Trial registration: not traceable Study design: double‐blind randomised clinical trial Setting and centres: 3 hospitals paediatric departments, Isfahan University of Medical Sciences, Isfahan, Iran Dates of study: January 2010 to December 2011 Duration of study: until child was discharged Inclusion criteria: acute onset of respiratory distress, positive wheezing on physical examination, chest radiograph compatible with bronchiolitis, aged < 12 months, and RDAI score of at least 5 Exclusion criteria: family history of asthma; chronic pulmonary, cardiac, neurologic and oncologic disease; previous use of glucocorticoids, bronchodilators or monoamine oxidase inhibitors (MAOI); tachycardia exceeding 200 beats per minute; tachypnoea exceeding 100 breaths per minute
Participants	Randomised: 125 infants. 2 study arms: magnesium sulphate + epinephrine 63; epinephrine 62 Analysed: magnesium sulphate + epinephrine 60; epinephrine 62. Three children in the magnesium sulphate + epinephrine group, and two children in the epinephrine group were subsequently withdrawn because of deteriorating clinical status Analysis for follow‐up: there was no follow‐up of participants Age: mean (SD) age was 5.2 (2.1) months in the magnesium sulphate + epinephrine group; 4.8 (3.2) months in the epinephrine group Gender distribution: (male:female) was 34:26 in the magnesium sulphate + epinephrine group; 38:22 in the epinephrine group Baseline clinical severity score: mean (SD) 11.4 (2.7) in the magnesium sulphate plus epinephrine group; 11 (2.7) in the epinephrine group Baseline heart rate: mean (SD) 104 (5) in the magnesium sulphate + epinephrine group; 104 (4) in the epinephrine group Baseline O₂ saturation: mean (SD) 88 (1) in the magnesium sulphate + epinephrine group; 87 (1) in the epinephrine group
Interventions	Intervention: 40 mg/kg magnesium sulphate (3.25%) and 0.1 mL/kg epinephrine (1/1000) mixed with normal saline nebulisation Comparator: 0.1 mL/kg epinephrine (1/1000) mixed with normal saline nebulisation Concomitant treatment in both groups: 0.1 mL/kg epinephrine (1/1000) mixed with normal saline nebulisation All groups received 3 doses of each medication at 20‐minute intervals, and then every 4 hours
Outcomes	Planned outcomes: no protocol available Reported outcomes: primary outcome was length of hospital stay (defined as the time from the first study inhalation until discharge from the hospital, as recorded in the medical record for each child). Other outcomes were RDAI scores; oxygen saturation; heart rate; respiratory rate; and use of ventilatory support. All outcomes recorded at admission, first 20 minutes, second 20 minutes, third 20 minutes, after 4 hours, and then daily during hospitalisation
Notes	Funding source: supported financially by Child Growth and Development Research Center, Isfahan University of Medical Sciences, Isfahan, Iran Conflicts of interest: none
Risk of bias
Bias	Authors' judgement	Support for judgement
Allocation concealment (selection bias)	Low risk	Adequate methods of sequence generation and allocation concealment used. Random number tables and third party randomisation were used
Blinding (performance bias and detection bias) All outcomes	Low risk	Knowledge of allocations was never broken throughout the study, as stated by the trial authors
Incomplete outcome data (attrition bias) All outcomes	Low risk	3 children in the magnesium sulphate + epinephrine group and 2 children in the epinephrine group were subsequently withdrawn because of deteriorating clinical status
Selective reporting (reporting bias)	Low risk	The planned outcomes in the methods section were reported in the results section
Other bias	Low risk	None of the trial authors disclosed receipt of any grants, or funds, or shares from any pharmaceutical company. Authors reported no conflicts of interest