Allegations of widespread doping in athletics are “sensationalist and confusing”, according to the sport’s world governing body.
The Sunday Times
which it says reveals an “extraordinary extent of cheating”.
The IAAF, whose data was leaked, stressed the results referred to were not positive tests or proof of doping.
It also rejected the suggestion it had done nothing to act upon data showing “suspicious” results.
The Sunday Times and German broadcaster ARD/WDR obtained access to the results of 12,000 blood tests between 2001 and 2012.
An IAAF statement said: “Any reporting by the ARD and Sunday Times that the IAAF was negligent in addressing or following up the suspicious profiles is simply false, disappointing and misinformed journalism.
“In an attempt to catch and sanction the cheats in our sport, the IAAF has used every means available to it within the anti-doping framework it operates in.”
In a detailed response, it also denied the data was “secret” and said it had published a detailed analysis of it more than four years ago.
More to follow.