Track and field's governing body issued a 38-page response to allegations by British and German media outlets that it had ignored and tolerated rampant blood doping in the sport.
"The IAAF is not complacent about doping in its sport," the federation said. "It will continue to use every tool at its disposal to fight doping and protect clean athletes."
The statement was released a few days before IAAF President Sebastian Coe faces a British parliamentary hearing into the doping allegations made by The Sunday Times newspaper and German broadcaster ARD.
"The IAAF cannot sit idly by while public confidence in its willingness to protect the integrity of its sport is undermined by allegations of inaction/incompetence that are based on bad scientific and legal argument," it said.
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The IAAF singled out the case of Radcliffe, saying the three-time London Marathon winner was publicly accused of doping "based on the gross misinterpretation of raw and incomplete data."
The IAAF said it followed up by testing Radcliffe's urine and blood samples for EPO and blood transfusions, and all the results came back negative. It said it collected 14 blood samples from Radcliffe for screening purposes from 2001 to 2008.
"The circumstances in which Ms. Radcliffe came to be publicly accused are truly shocking," the IAAF said, adding that she was "hounded remorselessly" by the media until she felt compelled to publicly defend herself.
"Obviously there's been damage done to my reputation, and to the reputation of the sport, and that's why I took the stand I did against this," Radcliffe said Friday after the release of the IAAF statement. "Yes, it was only me being singled out but there are a lot of other innocent, clean athletes who have or may produce an atypical value at some point.
Britain's national anti-doping agency said it also reviewed Radcliffe's test results and agreed there was no case against her.