A diabetes paper that received quite a bit of media attention when it was published in June 2013 was retracted and reissued to fix data errors shortly after publication.
The paper, which showed a steep decline in mortality rates for diabetics in Ontario, Canada, and the UK between 1996 and 2009, was republished in December 2013, with the same conclusion and the errors corrected.
Here’s the retraction notice for “Mortality trends in patients with and without diabetes in Ontario, Canada and the UK from 1996 to 2009: a population-based study”:
The authors wish to retract this article, published online on 22 June 2013, because a calculation error has become apparent. Some of the data in Table 2 and ESM Tables 4 and 5 are incorrect, as are some of the secondary conclusions. The authors regret this error and confirm that the main conclusion remains valid.
This retraction is intended to maintain the integrity of material published in Diabetologia and the journal acknowledges the full cooperation of the authors.
A corrected version of the paper is available at: DOI 10.1007/s00125-013-3063-1.
Here’s the abstract from the corrected paper, which has now been cited twice, according to Thomson Scientific’s Web of Knowledge:
The aim of this study was to determine the contemporary rate ratio of mortality and changes over time in individuals with vs without diabetes.
Annual age- and sex-adjusted mortality rates were compared for adults (>20 years) with and without diabetes in Ontario, Canada, and the UK from January 1996 to December 2009 using The Health Improvement Network (THIN) and Ontario databases. The total number of individuals evaluated increased from 8,757,772 in 1996 to 12,696,305 in 2009.
The excess risk of mortality for individuals with diabetes in both cohorts was significantly lower during later vs earlier years of the follow-up period (1996-2009). In Ontario the diabetes mortality rate ratio decreased from 1.90 (95% CI 1.86, 1.94) in 1996 to 1.51 (1.48, 1.54) in 2009, and in THIN from 2.14 (1.97, 2.32) to 1.65 (1.57, 1.72), respectively. In Ontario and THIN, the mortality rate ratios among diabetic patients in 2009 were 1.67 (1.61, 1.72) and 1.81 (1.68, 1.94) for those aged 65-74 years and 1.11 (1.10, 1.13) and 1.19 (1.14, 1.24) for those aged over 74 years, respectively. Corresponding rate ratios in Ontario and THIN were 2.45 (2.36, 2.54) and 2.64 (2.39, 2.89) for individuals aged 45-64 years, and 4.89 (4.35, 5.45) and 5.18 (3.73, 6.69) for those aged 20-44 years.
The excess risk of mortality in individuals with vs without diabetes has decreased over time in both Canada and the UK. This may be in part due to earlier detection and higher prevalence of early diabetes, as well as to improvements in diabetes care.
The managing editor of the journal gave us a few more details:
What happened was basically as follows:
- After online (but not print) publication a reader contacted the authors with a question related to the paper. This led the authors to realise there was a calculation error which affected data in table 2 and the supplementary material, as well as the secondary conclusions of the paper
- The authors alerted us to this and asked to correct their paper. They sent a version of the paper in which the required corrections were highlighted.
- Our editor evaluated the requested changes and approved the corrections having verified that main conclusions were not affected.
- Given the extent of the changes required the authors requested permission to print a ‘clean’ version of their paper rather than an erratum. The only way to achieve this was for us to retract the paper with the incorrect data and then publish the corrected article in its entirety.
- This course of action was approved by our publisher, Springer, and their quality assurance team because the miscalculation directly affected the results of the paper.
Hat tip: Rolf Degen