Ref (type)	Population	Outcome, Interventions	Results and statistical analysis	Effect size	Favours
Sleepiness
Systematic review	27 people Data from 1 RCT	Mean Epworth Sleepiness Scale (ESS) score (see table 3 ) 7.8 with bi-level positive airway pressure 8.0 with CPAP	WMD –0.20 95% CI –3.44 to +3.04 See further information on studies for methodological weaknesses		Not significant
Quality of life
RCT	104 people with OSAHS (mean AHI about 40; see table 2 ) non-compliant with CPAP therapy (defined as using CPAP for less than 4 hours per night)	Quality of life (mean Functional Outcomes of Sleep Questionnaire [FOSQ] score; see table 3 ) 90 days 15.7 with bi-level positive airway pressure 15.8 with CPAP	Reported as not significant P value not reported		Not significant