How much longer must we wait for proper epidemiological studies?

Recognition nearly 20 years ago of a high incidence of spinal cord injuries in rugby union players1 led eventually to changes in the rules in most rugby playing countries. New Zealand changed its rules in 1980 and 1984; Britain in 1979, 1984, and 1985; Australia in 1985; and South Africa in 1990. The consensus is that these changes have produced the desired effect, but how robust is the evidence? The week in which the Rugby World Cup begins in South Africa seems an apt time to address this question.

Silver's study of 63 spinal cord injuries in rugby union players between 1952 and 1982 was important in identifying mechanisms of injury in a representative sample of rugby players.2 But it was not a study of incidence. Two further studies by him included all spinal cord injuries in rugby players treated in eight spinal units in England and Wales between 1980 and 1986.3 4 By this time the incidence of spinal cord injuries should have begun to fall if the actions taken by the English Rugby Football Union had been effective.

These data show that, although the annual incidence of spinal cord injuries at Stoke Mandeville Hospital fell steadily from a peak of …