Analysis
PREDIMED trial of Mediterranean diet: retracted, republished, still trusted?
BMJ 2019; 364 doi: https://doi.org/10.1136/bmj.l341 (Published 07 February 2019) Cite this as: BMJ 2019;364:l341Linked opinion
A Mediterranean diet trial’s retraction and republication leaves a trail of questions
Re: on PREDIMED trial
We take notice of the comments by Agarwal and Ioannidis on our recent re-publication of the PREDIMED trial in The New England Journal of Medicine (NEJM) and related publications. However, most of the issues that they now mention were already addressed in the NEJM paper including the 99-page Supplementary Appendix, which is freely available at www.nejm.org/doi/suppl/10.1056/NEJMoa1800389/.
We have also published corrections of minor aspects in reports of secondary outcomes in other PREDIMED papers. Of note, prior to republication in the NEJM, the new manuscript underwent rigorous and extensive reviews by editors and peer reviewers, including external and independent statistical reviewers. Seldom has a report of a randomized clinical trial undergone such an exhaustive scrutiny as PREDIMED has, despite which the results have stood essentially unchanged from those published initially. This should increase trust, not distrust, in the performance and conclusions of the PREDIMED trial. We have also addressed issues related to data sharing (page 93 of the above-mentioned supplement).
Both the strengths and limitations of the PREDIMED trial were clearly acknowledged in our NEJM paper as well as in revisions of secondary outcome papers and some observational analyses in other journals with virtually no changes in results or conclusions. We will provide detailed response to additional key points raised by Agarwal and Ioannidis in the coming weeks, which will be posted in the section “Questions and Answers” of www.predimed.es.
Sincerely,
The PREDIMED trial investigators
Competing interests: No competing interests