Science journal Nature has apologised to Chinese swimmer Ye Shiwen and its readers for a controversial article that some interpreted as supporting unproven doping accusations against her. In an editor's note released on its website on Monday, Nature admitted an error in its data about Ye's performance, and the 'absence of a more detailed discussion' of statistics. 'This article has drawn an extraordinary level of outraged response,' the note said. 'The story's intention as an Explainer was to examine how science can help resolve debates over extraordinary performances.' Nature explained why it had changed the subtitle of the story online from the original ''Performance profiling' could help catch sports cheats' to ''Performance profiling' could help dispel doubts'. 'The original version of the title was unfair to the swimmer Ye Shiwen and did not reflect the substance of the story. We regret that the original appeared in the first place,' it said. 'We also regret that the original story included an error about the improvement in Ye's time for the 400-metre individual medley: she improved by 7 seconds since July 2011, not July 2012.' The note continued by saying the article 'gave the impression that we were supporting accusations against her ... This was emphatically not our intention. For that, we apologise to our readers and to Ye Shiwen.' On Friday, in response to an e-mail from the South China Morning Post, a Nature spokesman said the journal would 'stand by' the story. 'We are sorry the story caused so much outrage but we stand by it and reject accusations of bias,' he wrote. The author of the article has been criticised for cherry-picking data. Ewen Callaway, a reporter who covers biomedical issues, called Ye's performance at the Olympic Games 'anomalous' because she posted a time more than seven seconds faster than at her last major event. In response to the claim, an associate professor at the University of Kansas, Jun Huan, examined data on more than 2,600 swimmers, covering more than 40,000 performance records between 2007 and 2012. He reached a different conclusion from Callaway. 'For example Stephanie Rice, the 2008 Beijing Olympic 400-metre individual medley gold medallist, improved her performance from the 2007 World Championship to the 2008 Olympic [Games] by about 12 seconds. In another example, Kirsty Coventry, the 2008 Beijing Olympic 400-metre individual medley silver medal winner, improved her [time] from the 2007 All-Africa Games to the 2008 Olympic [Games] by about 10 seconds,' Dr Huan wrote on his website. 'We have found half a dozen cases where elite 400-metre individual medley athletes have [seen] more than a seven-second performance boost in a year.' Lai Jiang , a doctoral student at the University of Pennsylvania's chemistry department, criticised the comparison of Ryan Lochte's last 50 metres to Ye's as a 'textbook example of 'cherry-picking' your data'. 'Failing to mention this strategic difference, as well as the fact that Lochte is 23.25 seconds faster (4:05.18) than Ye overall, creates the illusion that a woman swam faster than the best man in the same sport,' he wrote online. More than 1,000 Chinese researchers and students signed a letter to Nature demanding it apologise.