Paula Radcliffe has been declared innocent of blood doping by the IAAF.
Marathon world record holder Radcliffe had "categorically" denied any form of cheating after claiming she was implicated by a parliamentary hearing.
Athletics' governing body said: "She's been publicly accused of blood doping based on the gross misinterpretation of raw and incomplete data.
"There are clearly plausible explanations for the values in her profile that are entirely innocent."
Jesse Norman MP had suggested in a Commons Culture, Media and Sport Committee (CMS) hearing that London Marathon medallists and "potentially, British athletes" were under suspicion of providing suspicious blood samples, although Radcliffe was not named specifically.
Norman later said his comments were "taken out of context", and that he had not intended to implicate the 41-year-old.
The hearing came after the Sunday Times and German broadcaster ARD/WDR published allegations of suspected doping, having obtained the results of 12,000 blood tests from 5,000 athletes taken between 2001 and 2012.
The World Anti-Doping Agency (Wada) said it was "very alarmed" by the allegations, and is currently investigating the claims.
However, in a statement published on Friday, the IAAF offered a complete defence of Radcliffe, and rebutted claims it had ignored evidence of cheating.
It said it could not "sit idly by while public confidence in its willingness to protect the integrity of its sport is undermined by allegations of inaction or incompetence that are based on bad scientific and legal argument".