Four out of five child car seats are still incorrectly fitted, according to the Road Safety Authority.
The authority has been running a campaign throughout the country to get people to check their child car seats are correctly fitted.
Its inspectors have found that 80% of the seats require "major" readjustment.
This means they represent the danger of a "major impact" in the event of a crash.
Over 25,000 child seats have been checked since 2013. The RSA said 2% of the seats examined have been deemed totally unfit for purpose.
In total, 14 children under the age of 15 died on Irish roads last year - 36.7% of all child deaths in Ireland as a whole, according to the RSA.
Of those 14 killed, seven were pedestrians and seven were passengers.