Jackson 2022.

Study characteristics
Methods	Randomised, parallel‐group, placebo‐controlled study
Participants	290 total participants (age 6‐17 years) Main inclusion criteria: at least 2 exacerbations in the previous year blood eosinophils ≥ 150 cells/µL
Interventions	Mepolizumab administered SC every 4 weeks, 40 mg for 6‐11 year‐olds and 100 mg for 12‐17 year‐olds for 52 weeks
Outcomes	Primary Asthma exacerbations treated with systemic corticosteroids Secondary Time to first exacerbation Lung function Quality of life Composite Asthma Severity Index (CASI)
Notes	Conference abstract. NCT03292588
Risk of bias
Bias	Authors' judgement	Support for judgement
Random sequence generation (selection bias)	Low risk	Allocation is random
Allocation concealment (selection bias)	Unclear risk	Details not provided
Blinding of participants and personnel (performance bias) All outcomes	Low risk	ClinicalTrials.gov reports triple masking (participant, care provider, investigator)
Blinding of outcome assessment (detection bias) All outcomes	Low risk	ClinicalTrials.gov reports triple masking (participant, care provider, investigator)
Incomplete outcome data (attrition bias) All outcomes	Unclear risk	Details not provided
Selective reporting (reporting bias)	Unclear risk	Challenging to assess reporting bias from a short abstract