LONDON • World athletics' governing body blocked the publication of a report that showed that as many as a third of the world's top athletes admitted using banned performance-enhancing techniques, Britain's Sunday Times reported.

The authors of the report told the British newspaper that the International Association of Athletics Federations (IAAF) blocked publication of the study, which was carried out four years ago. But the IAAF responded by saying there was nothing new about these revelations.

"The IAAF's delaying publication for so long without good reason is a serious encroachment on the freedom of publication," the University of Tuebingen in Germany, which carried out the research, said in a statement according to the paper.

Researchers from the university were given access to athletes at the 2011 World Championships in South Korea and concluded that between 29 and 34 per cent of the 1,800 competitors had violated anti-doping rules in the previous 12 months.

"These findings demonstrate that doping is remarkably widespread among elite athletes, and remains largely unchecked despite current biological testing programmes," the report concluded.

The IAAF issued a statement denying it had suppressed publication of the document.

"This is not a new story, having first been raised on German TV in 2013, and those concerns were addressed by the IAAF at the time," said the statement.

"The study in question was a social science-based survey conducted by Wada and a team of researchers at the athletes' village in Daegu.

"The purpose of the study was to assess the reliability of potential new methods of evaluating the prevalence of doping in sport using more of a social science approach (randomised-response survey).

"The survey was intended to be extended to multi-sport events and no publication was ever evoked."

The study was funded by the World Anti-Doping Agency (Wada), but it gave the IAAF power to veto publication in exchange for access to the athletes at Daegu.

After the study, the researchers were told to sign a confidentiality agreement to prevent them speaking out about the findings but they have now criticised the IAAF for suppressing the report.

"The IAAF is blocking it. I think they are stakeholders with Wada and they just blocked the whole thing," lead author Rolf Ulrich said.

However, the IAAF refuted suggestions any veto ever took place.

AGENCE FRANCE-PRESSE