Study designs of evaluations included in the review
To be eligible, studies needed to be double-blind randomised controlled trials (RCTs). However, one single-blind RCT was included in the review. Case reports and open studies were excluded. Both parallel-group and crossover trials were included in the review.
Specific interventions included in the review
Eligible studies investigated drug treatments or oral devices compared with a placebo. The treatments used in the included studies comprised drugs (bromocriptine, L-dopa, propranolol, clonidine, clonazepam, tryptophan and amitriptyline) and oral devices (mandibular advancement device (MAD), occlusal splints and palatal splints). Treatment duration ranged from a single dose to 4 weeks.
Participants included in the review
No explicit inclusion criteria were stated. It appeared that studies of participants with SB were eligible for inclusion in the review.
Outcomes assessed in the review
To be eligible, studies needed to use electromyographic recordings. Some studies recorded the electromyographic signal together with polygraphic sleep recordings, whilst others used ambulatory devices.
How were decisions on the relevance of primary studies made?
The authors did not state how the studies were selected for the review, or how many reviewers performed the selection.