Former WADA president Dick Pound says the second part of an independent commission's report into corruption in athletics will stun the world.
Pound heads the commission that has already revealed systematic doping in Russian athletics, leading to the nation being suspend from competition by the IAAF - a ban that could see athletes miss the 2016 Olympic Games in Rio de Janeiro.
The second part of the investigation delves into the IAAF and has been held back after the launch of a French police investigation into its former president Lamine Diack and ex-head of anti-doping Gabriel Dolle.
But Pound, who expects the new information to be released early next year, believes it will cause huge a stir.
"When we release this information to the world, there will be a wow factor," he told The Independent.
"People will say: 'How on earth could this happen?'
"It's a complete betrayal of what the people in charge of the sport should be doing."
He added regarding the report's release date: "It would be nice to have it done in 2015, but it looks more likely to be January.
"One fear is that if we issue it on the Friday before Christmas for example no one will notice it and we want to have the maximum impact and deterrent."