ID (Registry)	Title	Review Question(s)
CRD42017078285 (PROSPERO)	The efficacy of bone-anchored hearing implants in children	What is the efficacy of bone-anchored hearing implants in children with an indication for a percutaneously applied bone-conduction device?
CRD42017080811 (PROSPERO)	Quality of life and hearing with the use of middle ear implant: a systematic review and meta-analysis	In patients with conductive hearing loss, mixed hearing loss or unilateral hearing loss, how do middle ear implants compare to pre-implantation hearing aids in quality of life and hearing?
CRD42017075696 (PROSPERO)	Bone-anchored hearing aids skin complications in the pediatric population: systematic review with meta-analysis	How does the rate of skin complications of percutaneous bone-conduction implants compare to transcutaneous bone-conduction implants? How does the rate of implant loss of percutaneous bone-conduction implants compare to transcutaneous bone-conduction implants? How does the rate of re-operation related to implantation of percutaneous bone-conduction implants compare to transcutaneous bone-conduction implants?
CRD42017079675 (PROSPERO)	Quality of life and hearing after the implant of bone anchored hearing aid: a systematic review and meta-analysis	In patients with conductive hearing loss, mixed hearing loss or unilateral hearing loss, how do bone-anchored hearing aids compare to pre-implantation hearing aids in quality of life and hearing?