The prestigious Lancet medical journal said it is bolstering its scientific review process after being forced to retract a study into the effects of an anti-arthritis drug on COVID-19 patients.

The research, released in May, prompted the World Health Organization to pause its trials of hydroxychloroquine after the results suggested it had no positive effects on hospitalised individuals and may in fact increase the likelihood of death.

The study also whipped up fresh controversy over hydroxychloroquine, which has been endorsed by public figures—including US President Donald Trump—despite concerns over side effects and a lack of evidence that it is effective.

The paper in question was retracted after a group of experts raised "both methodological and data integrity concerns" about it.

These included a lack of information about the countries and hospitals that contributed to the data provided by Chicago-based healthcare data analytics firm Surgisphere.

In a comment piece published late Thursday, The Lancet said the retraction had pushed it "to examine... peer-review processes to identify ways of further reducing risks of research and publication misconduct".

Peer-reviewed research is checked by a collection of other experts before publication.

The Lancet said it was introducing new review measures including ensuring at least one reviewer being knowledgeable on the area of research in question and expanded data sharing.

"As trusted sources of information, the Lancet journals are committed to ensuring that our editorial processes will continue to be as robust as possible," it said.

© 2020 AFP