RETRACTION: Prioritising primary care patients with unexpected weight loss for cancer investigation: diagnostic accuracy study

Following BMJ’s expression of concern (BMJ 2024;384:q688, doi:10.1136/bmj.q688)¹ issued for this paper (doi:10.1136/bmj.m2651) on 25 March 2024, this article has now been retracted by BMJ due to the identification of an error in the authors’ approach to the research.²

The authors informed BMJ that some patients were excluded from the study because their healthcare records contained a code that was not associated with weight loss. Sometime later, however, some of these patients are likely to have had a code included in their healthcare record that was associated with unintended weight loss and cancer. This created an unintended selection bias in the work; some patients were excluded from the study who should have been included. This caused the study to underestimate the prevalence of cancer in the general primary care population.

Rectifying this error results in substantially more patients being included in the study, and reanalysis changes the study’s key results and messages. Consequently, the authors and BMJ have agreed to retract this paper. An updated version of this paper has been published in The BMJ (doi:10.1136/bmj-2024-080199).³