Quality assessment of systematic reviews on the efficacy of oral appliances for the management of obstructive sleep apnea

Objectives: To asses the methodological quality of published systematic reviews (SRs) about the efficacy and effectiveness of oral appliances (OA) in the management of obstructive sleep apnea (OSA).
Methods: SRs with or without meta-analyses that evaluated the efficacy or effectiveness of OA therapy on the treatment of OSA in human subjects of all age groups were sought. Multiple electronic databases were searched for articles published in any language from the database’s inception until February 2015. Two reviewers independently selected and then assessed the methodological quality of the studies using the Assessment of Multiple Systematic Reviews (AMSTAR) measurement tool.
Results: Fifteen SRs met the inclusion criteria. They included SRs only (n=5) and SRs with meta-analyses (n=10). Eight SRs were of medium quality and seven were of high quality. The major limitations in those SRs were failing to reference the excluded studies (53.3%), lack of use of a valid tool or criteria to assess the quality of included studies (20.0%), lack of publication bias assessment (46.7%), and absence of conflicts of interest reporting (93.3%).
Conclusions: Overall, SRs on the efficacy of OA in the management of OSA were conducted with acceptable methodological quality. High AMSTAR scores should not be extrapolated as a proxy of the methodological quality of the included evidence.