The National Registry of Medical Examiners: Ensures that medical examiners understand how FMCSA medical regulations and guidance apply to CMV drivers. Was created to enhance CMV driver health and reduce highway crashes. Information from NTSB crash investigations indicates that improper medical certification of CMV drivers with serious disqualifying medical conditions has directly contributed to fatal and injury crashes. All commercial drivers must be examined by a medical professional listed on the National Registry of Certified Medical Examiners.