The department for transport has not enacted recommendations made five years ago on mobility scooters, according to a Commons committee.
Anecdotal accounts of accidents involving "invalid carriages" as they are classified by the Highway Code are not enough, and more data must be recorded, said the transport select committee.
A comprehensive evidence base detailing the number and nature of accidents involving mobility scooters on UK roads and pavements would allow for the development of sound policy, the MPs said.
The DfT conducted a review in 2005 but ministers failed to act on its findings.
"Increasingly, mobility scooters are a vital aid for many people in the UK," said transport committee chair Louise Ellman.
"We welcome the independence that these vehicles can give people to go about their daily lives.
"However, we are concerned about the many reported accidents and injuries involving the scooters.
"The government does not have adequate data on either how many mobility scooters are in current use or on the number and type of accidents in which they might be involved.
"We welcome the department's current consultation but, unlike the previous review in 2005, the government must act on its conclusions."
