Three cars previously given top marks in safety trials in fact offer poor protection to occupants in rear-end shunts, follow-up tests have shown.
The Citroen C5, Ford Kuga and Peugeot 308 CC had all scored a maximum five stars in seat tests for the European New Car Assessment Programme (Euro NCAP).
But follow-up crash tests by car insurance repair research organisation Thatcham, found that the C5 scored only 0.57 points and the Kuga 0.44 - with zero for the Peugeot.
Models rated 'poor' included the Peugeot, Suzuki Splash, Daihatsu Terios, Hyundai i10 and Citroen Berlingo. Top performers were the Volvo XC60, Audi A4, Opel Insignia, Alfa Romeo Mito and Volkswagen Golf VI.
Thatcham director and Euro NCAP board member Andrew Miller said: "These results show a real need for some manufacturers to take a long hard look at their seat design.
"The new series of tests show that some seats previously thought to be adequate are just not offering motorists and their passengers' proper protection."
© Press Association 2008