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U.S. Department of Transportation U.S. Department of Transportation Icon United States Department of Transportation United States Department of Transportation

Effect of the Length of Medical Certification on Safety


Project Goal:

This project will assess whether drivers who are medically certified for less than 2 years have an effect on safety performance.



FMCSA relies on the certified medical examiner (ME) to assess and determine if the commercial motor vehicle (CMV) driver meets the physical qualification requirements cited in 49 CFR 391.41. The maximum time a medical examiner can certify a driver is 2 years. The ME can, however, certify for a period of time less than 2 years. Drivers with specific medical conditions require more frequent certification. For example, drivers with the following conditions can only be certified for a maximum of 1 year per the regulatory requirements: • drivers grandfathered under 391.64 as part of the original vision waiver program • drivers with insulin-treated diabetes mellitus and qualified under the diabetes standard • driving in exempt intra-city zone If the ME determines that a condition requires more frequent monitoring, the ME may certify the driver for 3 months, 6 months, 1 year, or any other timeframe that is less than 2 years.



The analysis will use data from the National Registry of Certified Medical Examiners (National Registry) to compare the length of the time the driver was medically certified to the crash data available in Motor Carrier Management Information System (MCMIS). Research Question: What is the prevalence and crash risk of drivers who are medically certified for less than 2 years compared to drivers who are medically certified for 2 years? The results should be reported for drivers that are certified for 3 months, 6 months, 1 year, or other timeframes.





Kickoff Meeting



Statistical Analysis



Draft Final Report



Final Report





Total Funding: $ 221,172.60