Misleading BMJ news releases may be one reason journalists report on more observational studies

Just a few days ago, a paper in the journal PLoS One, “Media Coverage of Medical Journals: Do the Best Articles Make the News?” showed how journalists are more likely to report on observational studies than on randomized clinical trials.  The authors suggest this shows a systematic bias to report on weaker evidence.

And here’s one reason why that may happen.

This week the BMJ sent out a news release on a paper from the Annals of the Rheumatic Diseases, one of the specialist journals it publishes. And I’ve been waiting for days to address it – waiting for the journal’s embargo time to pass so that I’m not violating that sacred trust.

The headline of the news release:  HRT cuts risk of repeat knee/hip replacement surgery by 40%.


Nope.  Sorry, BMJ news release writers.  That’s an overstatement, to be kind.  An inaccuracy, to be accurate. That’s not what the study showed, because it wasn’t equipped to show that anything “cut risk.”  Proof of cutting risk would be proof of cause and effect.  And the observational study in question can’t do that.

Don’t blame the authors of the journal article. They didn’t use cause-and-effect language.  They concluded: “HRT is associated with an almost 40% reduction.”  (My emphasis added.) That’s the way you describe the results of an observational study. That’s what we try to teach journalists and the public with a primer that’s been on our site for years. Maybe the BMJ should have its news release writers read it.

The researchers went even further, for any writer – journal news release writers included – who bothered to read the study.  The research team wrote: “The main limitation of this study is its observational nature.”

To be clear, this was a large study with long followup.  This could be a head-turner in medical circles.

But it still is what it is – a study that can only show statistical association.

And association ? causation.

We’ve written about this problem with BMJ news releases in the past, and will continue to do so until they get it right.  Past examples:

As I wrote in one of these posts:  Journals could help lift all ships – or they can (and sometimes do) help us all drown in a daily tsunami of global miscommunication about health news.


Follow us on Twitter:



and on Facebook.



You might also like

Comments (17)

Please note, comments are no longer published through this website. All previously made comments are still archived and available for viewing through select posts.

Wendy Sue Swanson

January 22, 2014 at 6:05 pm

Thanks for writing this. Have you ever heard from BMJ staff after writing these posts?

It would behoove academic journals to require primary authors to submit a summary of their work (for the public) and takeaways to be used by the media and for use on social media. I’ve mentioned this to a couple of editors or large journals. Not there yet but perhaps we will be soon.

Trish Groves

January 23, 2014 at 12:15 pm

Hi Gary

Thanks for picking this up. With more than 50 journals, BMJ issues a lot of press releases every year (available here http://group.bmj.com/group/media/bmj-press-releases). If one slips below the usual standard we want to know about it, and we appreciate the work you and others do to keep our feet to the fire.

Just a few points of clarification:

* as you rightly said in your blog, the paper was not in The BMJ (http://www.bmj.com/) but in Annals of Rheumatic Diseases (http://ard.bmj.com/), one of more than 50 journals published by BMJ (the company http://company.bmj.com/)

* however, some of your audience – particularly on Twitter – have got the wrong end of the stick, thinking that the paper or press release were about The BMJ. Understandable, but worth correcting – I’ll do so on Twitter

* I check all press releases for research published in The BMJ and BMJ Open, the two journals I work for

* All press releases for all of BMJ’s journals are written by approved by the papers’ authors and are accompanied by the full paper, any linked editorial, and the authors’ contact details. See BMJ’s media release policy for details: http://www.bmj.com/about-bmj/resources-media

I’ll add that our press officers are very experienced and skilled, and that we all work hard to ensure good, accurate, transparent, and full reporting of research. And that I’ve responded here before to criticism: https://www.healthnewsreview.org/2012/03/bmj-news-releases-observational-studies-overstatement/
I hope that – as you did last time – you’ll read my response as a genuine acknowledgement of the constructive criticism, rather than defensive behaviour.


Dr Trish Groves
Head of Research, The BMJ
Editor-in-Chief, BMJ Open


    Gary Schwitzer

    January 23, 2014 at 12:27 pm


    Thanks for your response and acknowledgement of our criticism.

    You are correct, I believe, that some folks on Twitter may have misinterpreted what I wrote, despite my attempt to be clear about the fact that the paper was not in The BMJ but in the Annals of Rheumatic Diseases – also published by BMJ (the company).

    It is perhaps inevitable that an occasional news release “slips below the usual standard.” But given the repeated instances I’ve highlighted on this topic of news releases about observational studies, I would hope that BMJ-group-wide training could reduce the chance and number of slips. And perhaps other steps could be taken to ensure that the news release is, indeed, a true reflection of the researchers’ work – including limitations.

Trish Groves

January 23, 2014 at 12:16 pm

Uh oh; I meant:

All press releases for all of BMJ’s journals are written by experienced press officers and then approved by the papers’ authors…



Trish Groves

January 23, 2014 at 3:32 pm

Here’s the article, with the press release posted alongside it:


Terry Murray

February 4, 2014 at 12:31 am

Re comment by Wendy Sue Swanson that “it would behoove academic journals to require primary authors to submit a summary of their work (for the public).”

Possibly. But many of these authors are actually incapable of summarizing their work for a lay audience. I spent 10 years on the animal care committee of a major Toronto teaching hospital. We required researchers to provide a “lay summary” with their submission to the committee. In that time, I can count on the fingers of one hand the number of researchers who wrote lay summaries that included the species of animal they were were using, why they chose the species and clearly explained (in brief) what their research was about. I asked a researcher on the committee, who seemed to have particular difficulty with lay summaries, what he told his kids about his work. “It’s very hard,” he said.

Based on that and 35 years as a medical journalist trying to get researchers to speak in words of one syllable (figuratively), I don’t think the lay summary idea is going to work.