Chadwick 1997.

Study characteristics
Methods	RCT Design: cross‐over with 3 arms. Duration of intervention is not stated.
Participants	Total participants: n = 15. Groups stratified according to FEV1 (over 70% and 40% ‐ 70%).
Interventions	Group 1: IS. Group 2: HS 3.5%. Group 3: hypotonic saline.
Outcomes	Change in FEV1 % predicted, nebulisation.
Notes	Abstract only. No sample size calculation stated.
Risk of bias
Bias	Authors' judgement	Support for judgement
Random sequence generation (selection bias)	Unclear risk	No detail provided.
Allocation concealment (selection bias)	Unclear risk	No detail provided.
Blinding of participants and personnel (performance bias) All outcomes	High risk	Stated as single blind, possibly assessors who were blinded due to difficulties in masking taste of intervention, but not clear.
Blinding of outcome assessment (detection bias) All outcomes	Unclear risk	Stated as single blind, possibly assessors who were blinded due to difficulties in masking taste of intervention, but not clear.
Incomplete outcome data (attrition bias) All outcomes	Unclear risk	No description of any dropouts given.
Selective reporting (reporting bias)	Unclear risk	Abstract only, no detail provided.
Other bias	Unclear risk	No sample size calculation stated. No washout period stated.