Ref (type)	Population	Outcome, Interventions	Results and statistical analysis	Effect size	Favours
Adverse effects
Systematic review	People with non-severe and severe OSAHS 4 RCTs in this analysis	Adverse effects with nasal CPAP with conservative treatment (sleep hygiene and advice about weight reduction) or oral placebo tablets Absolute results not reported
Systematic review	68 people with non-severe OSAHS Data from 1 RCT	Sleep disturbance 8/34 (24%) with CPAP 0/34 (0%) with control	OR 22.13 95% CI 1.22 to 400.93 RCT may have been underpowered to detect a difference in clinically important outcomes	Large effect size	control