Possible omission of information essential for conclusions in a research paper
ResourcesPossible omission of information essential for conclusions in a research paper
What is this about?
In 2013, a COPE member journal published a paper describing an observational study comparing two drugs (A and B) for the management of a chronic disease over a period of 10 years. The conclusion in the paper was that mortality was higher in group A (97 deaths) compared with the other group B (52 deaths) (hazard ratio 1.76, 1.22 to 2.53; P=0.003). This analysis was done after adjustment for a large number of confounders, and was approved by our statistical advisor. The authors of the papers did acknowledge that this was an observational study, and did state that residual confounding might be present.
In 2014 COPE received a letter of concern by a researcher, employed by the company selling drug A, who felt that the authors of the 2013 paper omitted essential information that might impact on the conclusions. It appears that the routine management of this disease has changed substantially over the 10 year period, and this should have been treated as a confounder for which statistical adjustments should have been made. This change in routine management of the disease is documented in a paper published in 2014, but the researcher felt that these authors were probably aware of this much earlier and should have disclosed this information during the review process of their 2013 paper.
In our initial response in July 2014 to the letter of concern, we asked the researcher who sent us the letter of concern to send us a detailed rapid response to the 2013 paper, which we could publish. We have also asked advice of our statistical advisor who reviewed the 2013 paper, and he acknowledged that this information might impact on the statistical calculations and thus the conclusions of the paper. But with the data available to him, he is not able to make a definitive assessment of how much impact it would have. He has suggested to put these questions to the authors of the 2013 paper.
