November 29, 2013

Roundup retraction

I’ve written before about the Seralini research that involved feeding glyphosate and GM corn to rats. Now, Retraction Watch is reporting that the paper will be retracted.

This is a slightly unusual retraction: typically either the scientist has a horrible realisation that something went wrong (maybe their filters were affecting composition of their media) or the journal has a horrible realisation that something went wrong (maybe the images were Photoshopped or the patients didn’t actually exist).

The Seralini paper, though, is being retracted for being kinda pointless. The editors emphasise that they are not suggesting fraud, and write

A more in-depth look at the raw data revealed that no definitive conclusions can be reached with this small sample size regarding the role of either NK603 or glyphosate in regards to overall mortality or tumor incidence. Given the known high incidence of tumors in the Sprague-Dawley rat, normal variability cannot be excluded as the cause of the higher mortality and incidence observed in the treated groups.

Ultimately, the results presented (while not incorrect) are inconclusive, and therefore do not reach the threshold of publication for Food and Chemical Toxicology. 

They’re certainly right about that, but this is hardly a new finding. I’m not really happy about retraction of papers when it isn’t based on new information that wasn’t easily available at the time of review. Too many pointless and likely wrong papers are published, but this one is being retracted for being pointless, likely wrong, and controversial.

 

[Update: mass enthusiasm for the retraction is summarised by Peter Griffin]

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Thomas Lumley (@tslumley) is Professor of Biostatistics at the University of Auckland. His research interests include semiparametric models, survey sampling, statistical computing, foundations of statistics, and whatever methodological problems his medical collaborators come up with. He also blogs at Biased and Inefficient See all posts by Thomas Lumley »

Comments

  • avatar
    megan pledger

    I think they should give some justification in terms of power calculations in order to retract the paper. Otherwise, it just sets up another barrier to getting null-result articles into journals.

    “Normal” variability can never be exluded from making a non-significant result appear significant because – although it’s unlikely – it’s not impossible, that “normal” variability will through up an abnormal sample.

    11 months ago Reply

  • avatar
    Martin Kealey

    Unless they suspect some bias in the data, then the raw data would still be useful to incorporated into some future meta-survey; combine enough samples and some valid conclusions might be reached.

    11 months ago Reply

    • avatar
      Thomas Lumley

      Yes, that’s the usual argument for publishing weak but valid studies.

      In this case, I think the sample size in each treatment condition is so small that there’s less than usual to be gained. Still, I wouldn’t have been upset if the study had been published with appropriately weak conclusions on these grounds.

      11 months ago Reply

  • avatar
    Martin Connelly

    The thing here is that Seralini is now regarded as a bit dodgy – and I suspect the Journal wants to make it known that it is having as little to do with him as possible

    11 months ago Reply

    • avatar
      Thomas Lumley

      Yes, I suspect that is the thing. But it’s scientifically unfortunate that that’s not what they say is the thing.

      They said they were retracting the paper because the study is underpowered and unconvincing. I suspect that is, at best, a very incomplete accounting of their actual reasons. I think it’s a Bad Thing for science if they don’t give their actual reasons for retracting a paper.

      11 months ago Reply

  • avatar
    Tim McMurphy

    What about the Monstanto studies? They used the same type or rat, less of them and only ran the study for 3 months. Will the journal retract those studies?

    I hope it goes to court to get the names of the “reviewers”. Without full disclosure how do we know there isn’t a blatant conflict of interest?

    Trust is in short supply and FCT just used up all theirs.

    11 months ago Reply

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