Statement of Concern

I am writing as Editor-in-Chief of the Journal to alert our readers about two similar articles recently published in the headache literature. Recently an author with expertise in Headache Medicine was conducting a literature search and the results included these two articles. What the author noted was the great similarity between the two articles causing some confusion as to why they appeared separately when they were so similar. This was brought to the attention of our editorial office and we have investigated this report following the protocols set forth by Committee on Publication Ethics guidelines. Our findings were reviewed and then discussed by the Publications Committee of the American Headache Society. The first article, Medication-Overuse Headache: Protocols and Outcomes in 149 Consecutive Patients in a Tertiary Brazilian Headache Center, was accepted for publication in Headache: The Journal of Head and Face Pain on July 25, 2016, and appeared in print in the January 2017 issue. While this article was under review the second article was submitted to Brain Sciences on May 24, 2016, accepted for publication on August 8, 2016 and published online August 15, 2016. The title of this second article is Medication-Overuse Headache: Differences between Daily and Near-Daily Headache Patients. These articles are not identical since they do address different aspects of medication overuse groups but they are very similar. We were able to determine that there was an approximately 35% direct text overlap (identicality) and much of the remaining content possessed similar meaning. A further indicator of overlap was to be found in the articles cited, the first 14 of which were identical and in the same order of citation. Of particular concern is the fact that while the authors utilized the same data set, neither article cites the other. These findings suggest “salami-slicing.” Salami-slicing is frowned upon in publishing. It occurs when one or more additional articles are created from one data set when a single article would be sufficient. The additional information published in subsequent articles does not add significantly to the literature and could have easily been included in the original publication. It also can cause confusion when literature searches are done, as occurred here. There is another issue. One of the authors, Dr. Stewart Tepper, has claimed inappropriate ascription of authorship in relation to the article published in Brain Sciences and has requested that his name be removed from that publication (and, in fact, his name has been removed). From correspondence between myself, as Editor-in-Chief, and the authors, I believe there may have been genuine misunderstanding that occurred possibly due to the great similarity between these manuscripts, which would serve to reinforce why we consider publications such as these to be problematic. In this issue of the Journal, please read an accompanying editorial discussing problems in the peer review process we encounter including plagiarism, self-plagiarism, salamislicing, and issues of inappropriate authorship (either claimed when not deserved, or perhaps worse, not claimed when authorship has occurred). Therefore, we are placing the Statement of Concern about the article Medication-Overuse Headache: Protocols and Outcomes in 149 Consecutive Patients in a Tertiary Brazilian Headache Center.