Ballmann 2002.

Methods	Open pilot trial. Cross‐over design. Duration: 2 treatment periods of 3 weeks, with a 3‐week washout period. Participants were assessed before and after each period.
Participants	14 participants (mean age 13.3 years) with mild to moderate pulmonary involvement. Withdrawals were not discussed within the paper.
Interventions	Treatment: 2 puffs salbutamol via a spacer prior to nebulisation of 2.5 mg dornase alfa once daily. Control: 2 puffs salbutamol via a spacer prior to nebulisation of 10 ml 5.85% HS once daily.
Outcomes	Change from baseline for FEV1 (% predicted), not clear if relative or absolute change.
Notes
Risk of bias
Bias	Authors' judgement	Support for judgement
Random sequence generation (selection bias)	Unclear risk	Described as randomised, but method not clear.
Allocation concealment (selection bias)	Unclear risk	Method unclear.
Blinding (performance bias and detection bias) All outcomes	High risk	Not blinded, due to the taste of the hypertonic saline.
Incomplete outcome data (attrition bias) All outcomes	Unclear risk	No discussion of whether ITT analysis performed. Withdrawals were not discussed within the paper.
Selective reporting (reporting bias)	Low risk	None identified.
Other bias	Low risk	Cross‐over design with washout period of 3 weeks which should be adequate for lung function to return to baseline.