Gotz 1995.

Study characteristics
Methods	RCT. Cross‐over design (2‐week washout between treatment arms). Location: single centre in Austria. Duration: 2x 4‐week treatment periods with 2‐week washout in between.
Participants	7 participants. Age and sex of the participants was not identified.
Interventions	2x daily IPV versus 2x daily PEP. 2x 4‐week periods of treatment, 2‐week washout between where there was no PT.
Outcomes	FEV1, PO₂. Measured before, 10, & 40 min after first treatment of the day once per week.
Notes	Abstract only, full paper not published as yet. Due to carryover effect the analysis was confined to the first treatment period; therefore this was analysed NOT as a cross‐over but a parallel study.
Risk of bias
Bias	Authors' judgement	Support for judgement
Random sequence generation (selection bias)	Unclear risk	Described as randomised, method not discussed.
Allocation concealment (selection bias)	Unclear risk	Not discussed.
Blinding (performance bias and detection bias) All outcomes	High risk	Blinding was not discussed.
Incomplete outcome data (attrition bias) All outcomes	Unclear risk	Data not reported, only generalised conclusions made.
Selective reporting (reporting bias)	Unclear risk	Not possible to compare trial protocol with the published abstract. No full paper available to exclude selective reporting bias.
Other bias	Unclear risk	Abstract only.