BUYING a child seat for your car can be a safety lottery, according to latest research.

Every year hundreds of children are killed or seriously injured in cars in the UK, but two out of three of these cases could be prevented by using a properly fitted child seat.

However, after rigorously testing 20 of the 20 top-selling seats, What Car? magazine has found that the levels of protection can very dramatically.

In the most comprehensive tests carried out in the UK, each seat was subjected to front and side-impact collisions, as well as being assessed for being easy to use.

In the front-impact tests, some seats only just scraped through and one actually failed.

Mothercare's new MX Sport infant carrier won the baby-seat category, and Britax seats scored highly, with the Cruiser Plus having the best high-back booster.

But Maxi Cosi's infant carrier broke under the strain, and the Graco Stella/Mothercare Paul Vogel Beep Beep failed to give adequate protection to the baby's head.