The BMJ's Expression of Concern: A Critical Look at a Controversial Stem Cell Study
The BMJ has issued an expression of concern regarding a paper claiming stem cell therapy can reduce the risk of heart failure. This move comes after a thorough investigation by sleuths and scientists, who identified a complete mismatch between the study data and the article itself.
As reported last week, the October 29 paper included results from a phase III clinical trial conducted in Shiraz, Iran. Critics quickly pointed out discrepancies in the data on PubPeer, with psychologist Nick Brown noting a curious repeating pattern of records in the dataset every 101 records.
The BMJ's expression of concern acknowledges issues with the data, including irregularities, discrepancies in age criteria, and undeclared conflicts of interest. Dorothy Bishop, a professor of developmental neuropsychology at Oxford University, was the first to highlight the paper's issues, specifically the claim that the study enrolled only patients under 65 years of age. However, the accompanying data revealed that 127 patients were older than 65, a significant mismatch.
On PubPeer, Bishop also pointed out potential conflicts of interest involving author Anthony Mathur, a researcher at Queen Mary University of London, who is a shareholder and trustee of the Heart Cells Foundation, a charity funding stem cell therapy administration.
The BMJ's notice states that the editors believe the trial may have breached accepted practices, and the results may not be reliable. They plan to investigate further and consider an auditable replacement dataset provided by the authors. Most of the authors, including corresponding author Armin Attar, are researchers at Shiraz University of Medical Sciences.
After the initial article's publication, sleuths continued to identify issues with the paper. Gideon Meyerowitz-Katz, a research fellow at the University of Wollongong in Australia, noted oddities in the data, such as nearly half of recorded heart rates being divisible by five. He also pointed out an unexpected pattern in patient temperatures, with 42 out of 311 recorded temperatures being exactly 36.2 degrees Celsius.
Retractions in The BMJ are rare, with the journal issuing its first retraction in 1989 and a total of just 12 articles retracted so far, according to the Retraction Watch Database.
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