Most children are in appropriate child restraints when travelling in cars, a Ministry of Transport survey shows.
The survey showed 93 per cent of children under 5 were in an appropriate child restraint, an increase of 1 per cent from the last survey in 2012.
More than half the children under 5 were in child seats and 20 per cent were in baby capsules or infant seats. Nineteen per cent of children under 5 were in booster seats and 0.8 per cent were in child harnesses.
Of the 7 per cent not in a safe child restraint, 3 per cent were wearing adult safety belts and another 3.2 per cent were unrestrained, including 1 per cent of children that were held on the knees of passengers.
Land Transport Safety Manager Leo Mortimer said: "Young children are some of our most vulnerable road users, and it's important they are in the right sort of child restraint to get the best protection."
Mr Mortimer said child restraints played a vital role in reducing the severity of injuries in the event of a crash.
"Adult safety belts are designed for adults, and do not fit children correctly. An adult safety belt alone, or holding a child on your knee, will not provide adequate protection in a crash.
"What type of restraint a child needs is going to depend on their age and size. Organisations such as Plunket are able to give parents and caregivers advice and support to make sure children are in an appropriate and correctly installed restraint."