A medical student in London, Jack Lawrence,
was among the first to identify serious concerns about the paper, leading to the retraction. He first became aware of the Elgazzar preprint when it was assigned to him by one of his lecturers for an assignment that formed part of his master’s degree. He found the introduction section of the paper appeared to have been almost entirely plagiarised.
It appeared that the authors had run entire paragraphs from press releases and websites about ivermectin and Covid-19 through a thesaurus to change key words. “Humorously, this led to them changing ‘severe acute respiratory syndrome’ to ‘extreme intense respiratory syndrome’ on one occasion,” Lawrence said.
The data also looked suspicious to Lawrence, with the raw data apparently contradicting the study protocol on several occasions.
“The authors claimed to have done the study only on 18-80 year olds, but at least three patients in the dataset were under 18,” Lawrence said.
“The authors claimed they conducted the study between the 8th of June and 20th of September 2020, however most of the patients who died were admitted into hospital and died before the 8th of June according to the raw data. The data was also terribly formatted, and includes one patient who left hospital on the non-existent date of 31/06/2020.”
There were other concerns.
“In their paper, the authors claim that four out of 100 patients died in their standard treatment group for mild and moderate Covid-19,” Lawrence said. “According to the original data, the number was 0, the same as the ivermectin treatment group. In their ivermectin treatment group for severe Covid-19, the authors claim two patients died, but the number in their raw data is four.”
Lawrence and the Guardian sent Elgazzar a comprehensive list of questions about the data, but did not receive a reply. The university’s press office also did not respond.
Lawrence contacted an Australian chronic disease epidemiologist from the University of Wollongong, Gideon Meyerowitz-Katz, and a
data analyst affiliated with Linnaeus University in Sweden
who reviews scientific papers for errors, Nick Brown, for help analysing the data and study results more thoroughly.
Brown
created a comprehensive document uncovering numerous data errors, discrepancies and concerns, which he provided to the Guardian. According to his findings the authors had clearly repeated data between patients.
“The main error is that at least 79 of the patient records are obvious clones of other records,” Brown told the Guardian. “It’s certainly the hardest to explain away as innocent error, especially since the clones aren’t even pure copies. There are signs that they have tried to change one or two fields to make them look more natural.”
Other studies on ivermectin are still under way. In the UK,
the University of Oxford is testing whether giving people with Covid-19 ivermectin prevents them ending up in hospital.
The Elgazzar study was one of the the largest and most promising showing the drug may help Covid patients, and has often been cited by proponents of the drug as evidence of its effectiveness. This is despite a peer-reviewed paper published in the journal Clinical Infectious Diseases in June finding ivermectin is “
not a viable option to treat COVID-19 patients”.
Meyerowitz-Katz told the Guardian that “this is one of the biggest ivermectin studies out there”, and it appeared to him the data was “just totally faked”. This was concerning because
two meta-analyses of
ivermectin for treating Covid-19 had included the Elgazzar study in the results. A meta-analysis is a statistical analysis that combines the results of multiple scientific studies to determine what the overall scientific literature has found about a treatment or intervention.
“Because the Elgazzar study is so large, and so massively positive – showing a 90% reduction in mortality – it hugely skews the evidence in favour of ivermectin,” Meyerowitz-Katz said.
“If you remove this one study from the scientific literature, suddenly there are very few positive randomised control trials of ivermectin for Covid-19. Indeed, if you get rid of just this research, most meta-analyses that have found positive results would have their conclusions entirely reversed.”