Accepted wisdom until now, drawn from annual testing statistics, was that ``maybe between 1 and 2 per cent of athletes who are tested are cheating'', agency director general David Howman said yesterday.

However, the agency is supporting research projects into the prevalence of doping among international-level athletes, with findings expected before the London Games open in July, Howman said.

Based on the initial results, ``we think those numbers are more in the double digits. Now that's a concern. If there is more than 10 per cent of the athletes in the world being tempted to take the shortcut by taking prohibited substances, then we've got an issue that is not being confronted as well as it should be.''

Howman stressed the research is not finalised and suggested it would be wrong to conclude that 10 per cent of athletes who compete in London might cheat.

``People go to the Olympic Games very well prepared for a big event, knowing if they are going to make a mistake it is the worst shame they can bring upon themselves, their family . . . (and) therefore less likely for people to take the shortcuts,'' he said.