UK Athletics made "reasonable" decisions in two internal reviews of allegations related to the controversial Nike Oregon Project run by Mo Farah's former coach Alberto Salazar, an independent report said on Friday.
The governing body held separate reviews into the now-defunct US project, first after allegations made in a BBC documentary in 2015 and again in 2017 after an interim US Anti-Doping Agency report was leaked.
US coach Salazar was banned for four years in October after being found guilty of doping violations following an investigation by the USADA.
The Nike Oregon Project was used as a training base by four-time Olympic champion Farah between 2011 and 2017.
Farah's relationship with Salazar has come under the microscope but there is no suggestion of any wrongdoing by the British long-distance runner.
In 2015, UK Athletics suspended its consultancy arrangement with Salazar but Farah was allowed to continue his coaching relationship with him, albeit with greater oversight in place.
UKA decided not to act in 2017, since the USADA advised action based on a leaked report would be "reckless".
Friday's independent report said that the UKA board was not informed by USADA or Salazar that charges for doping violations had been brought against him in June 2017.
"There should be no doubt, though, that had the board been aware of those proceedings and charges in 2017, it would have severed all relationships with Salazar at the time," the report said.
The governing body said barrister John Mehrzad's report had found its decisions "were reasonable at those times, taking into account the then circumstances and the information then available to UKA".
Nic Coward, who was appointed UK Athletics chairperson in January, said: "The depth of insight provided by this independent review is timely support for a number of changes that need to happen, and which we are already getting on with."
The report found that the 2015 internal review was "necessarily narrow" in scope because UKA was asked by USADA and UK Anti-Doping not to consider any doping-related allegations in the BBC programme.