Ref (type)	Population	Outcome, Interventions	Results and statistical analysis	Effect size	Favours
Daytime sleepiness
RCT	24 adults with loud snoring and severe OSAHS	Epworth Sleepiness Scale (ESS) score (see table 3 ) 2 weeks –3.8 with mandibular advancement devices –0.5 with control oral appliance	P <0.005	Effect size not calculated	mandibular advancement device
RCT Crossover design	85 people (including 14 women) with a mean ESS score of 11	Decrease in sleep latency (see table 3 ) 4 weeks with active mandibular advancement splint with inactive mandibular advancement splint Absolute results not reported	Decrease in sleep latency for active v inactive treatment: 1.2 minutes 95% CI 0.3 minutes to 2.1 minutes	Effect size not calculated	active mandibular advancement splint
RCT Crossover design	85 people (including 14 women) with a mean ESS score of 11	Improvement in ESS score with active mandibular advancement splint with inactive mandibular advancement splint Absolute results not reported	Improvement in ESS score for active v inactive treatment: 2 points 95% CI 1 point to 3 points	Effect size not calculated	active mandibular advancement splint
RCT Crossover design	85 people (including 14 women) with a mean ESS score of 11	Proportion of people with normal ESS score 82% with active mandibular advancement splint 62% with inactive mandibular advancement splint Absolute numbers not reported	P <0.01	Effect size not calculated	active mandibular advancement splint