Wenzel 2007.

Methods	Randomised, single‐blind, cross‐over study (participants not informed of order/setting). Statistical analysis based on Wicoxon methods (not specified if paired).
Participants	N = 20 participants completed and analysed (16 M/4 F). AHI: 45; ESS: 10.9 Inclusion criteria: new diagnosis of OSA (diagnosis established through polysomnography) Exclusion criteria: mixed or central apnoea
Interventions	CPAPexp (C‐Flex) versus fixed pressure CPAP Same machine delivered the different treatment pressure settings Study duration: 2 x 6 weeks
Outcomes	Machine usage (average hours used) AHI Symptoms (ESS)
Funding & conflicts of interest statements	Not provided
Notes
Risk of bias
Bias	Authors' judgement	Support for judgement
Random sequence generation (selection bias)	Unclear risk	Information not available
Allocation concealment (selection bias)	Unclear risk	Information not available
Blinding of participants and personnel (performance bias) Machine usage, symptoms, quality of life, withdrawal, adverse effects	High risk	Quote: "....randomised, single‐blinded cross‐over study"
Blinding of participants and personnel (performance bias) AHI, blood pressure, treatment pressure	Low risk	These outcomes unlikely to be affected by awareness of treatment group.
Blinding of outcome assessment (detection bias) Machine usage, symptoms, quality of life, withdrawal, adverse effects	High risk	Quote: "...single‐blinded cross‐over study"
Blinding of outcome assessment (detection bias) AHI, blood pressure, treatment pressure	Low risk	These outcomes unlikely to be affected by awareness of treatment group.
Incomplete outcome data (attrition bias) All outcomes	Low risk	All participants completed
Selective reporting (reporting bias)	Unclear risk	Information not available
Other bias	Low risk	No concerns identified