Master 2001.

Methods	Double‐blind RCT. Parallel design. Duration: at least 10 days. Single centre. Country: Australia.
Participants	51 participants with CF experiencing a protocol‐defined exacerbation with P. aeruginosa isolated from sputum. Participants with an FVC lower than 40% predicted were excluded. Intervention 1: 21 participants; mean (SD) age 16 (7) years. Intervention 2: 23 participants; mean (SD) age 15 (5) years.
Interventions	Intervention 1: IV ceftazidime 50 mg/kg/dose 3x daily and IV tobramycin 3 mg/kg/dose 3x daily. Intervention 2: IV tobramycin 9 mg/kg/day 1x daily.
Outcomes	Lung function (FEV1, FVC, FEF25‐75%), radiology, microbiology, adverse effects, time to next exacerbation.
Notes	UoA issues ‐ each participant contributed on average 3 episodes. Study was suspended for 3 months after 1 participant committed suicide, data from this period were not included. We shall seek to contact the study authors for individual study data.
Risk of bias
Bias	Authors' judgement	Support for judgement
Random sequence generation (selection bias)	Unclear risk	Described as randomised, stratified for age and disease progression, but no method detailed.
Allocation concealment (selection bias)	Unclear risk	No detail given.
Blinding of participants and personnel (performance bias) All outcomes	Low risk	Described as double blind with medical and nursing staff and participants blinded with identical syringes and placebos.
Blinding of outcome assessment (detection bias) All outcomes	Low risk	Described as double blind.
Incomplete outcome data (attrition bias) All outcomes	Low risk	Withdrawals were described and those participants who completed 10 days treatment but excluded for other reasons were included in an ITT analysis. The ITT analysis is described as not changing the effect of the short‐term analysis, but no data provided.
Selective reporting (reporting bias)	Unclear risk	Insufficient information.
Other bias	High risk	UoA issues ‐ each participant contributed multiple treatment episodes.