Car air bags 'make little difference' in saving lives

Air bags are far less effective than seat belts at preventing the deaths of motorists in road traffic accidents, according to a study published today.

The analysis, published in the British Medical Journal, of more than 51,000 fatal car crashes, in which driver and/or a passenger died, shows seat belts offer eight times more protection than air bags. Researchers in the US found that having an air bag reduced the risk of death by 8 per cent, whether the driver was wearing a seat belt or not.

Seat belts provided "much greater protection", reducing the risk of drivers dying by 65 per cent. Using a seat belt and having an air bag reduced the risk of death by 68 per cent.

Professor Peter Cummings, who led the research at the School of Public Health and Community Medicine, University of Washington, concluded: "Driver air bags offered relatively little benefit in road vehicle crashes compared with seat belts."

Woman did have more to gain from air bags than men, with a 12 per cent reduction in the risk of dying in a crash compared with a 6 per cent reduction for men. But the overall reduction in the risk of death assigned to air bags was substantially less than previous estimates of 10 to 14 per cent.

The study is one of several in the special edition of the BMJ, investigating how to reduce the 3,000 seriously injuries a day on the world's roads. Department of Transport figures show that 12,695 car drivers, 7,024 car passengers and 9,498 pedestrians were killed or seriously injured in traffic accidents across Britain in 2000.

Despite the casualty toll, the BMJ says the prevention of traffic accidents is "low on the list of public health priorities" both in the UK and across the world, with record low levels of funding for research. A letter to the journal also says that government plans to make speed cameras more visible could increase deaths and injuries on the roads because it will encourage speeding in areas free of the detectors.

Speed cameras have been shown to be effective in slowing traffic and, in some areas, deaths have been reduced threefold. Until now, they have been unobtrusive or hidden but they are to be made more visible by painting them yellow. Police forces will be banned from erecting dummy warning signs on roads where there are no cameras.

In his letter, Paul Pilkington, a specialist in public health at Avon Health Authority, Bristol, says the policy is a "mistake" because it will remove the uncertainty of where cameras are located. He said: "This uncertainty is one of the only means of discouraging widespread speeding."

Another study in the journal, from the University of Auckland in New Zealand, says deaths or injuries could be cut by almost 20 per cent if motorists avoided driving when they felt sleepy or were sleep-deprived. Researchers found that driving after five hours sleep or less increased the risk threefold of a car crash resulting in serious injury or death. Driving between 2am and 5am increased that risk by five and driving while feeling sleepy increased the risk eight times.