Is orthodontic research falling prey to obscure and predatory journals? A bibliometric study.

Aims: To evaluate where orthodontic research papers are published and to explore potential relationships between the journal of publication and the characteristics of the research study and authorship.

Methods: An online literature search of seven research databases was undertaken to identify orthodontic articles published in English language over a 12-month period (1 January-31 December 2022) (last search: 12 June 2023). Data extracted included journal, article, and author characteristics. Journal legitimacy was assessed using a ternary classification scheme including available blacklists and whitelists, cross-checking of indexing claims and history of sending unsolicited emails. The level of evidence (LOE) of all included studies was assessed using a modified Oxford LOE classification scale. Univariable and multivariable ordinal logistic regression analyses were performed to examine possible associations between the level of evidence, journal discipline, and authorship characteristics.

Results: A total of 753 studies, published by 246 unique journal titles, were included and further assessed. Nearly two-thirds of orthodontic papers were published in non-orthodontic journals (62.8%) and over half (55.6%) of the articles were published in open-access policy journals. About a fifth of the articles (21.2%) were published either in presumed predatory journals or in journals of uncertain legitimacy. Journal discipline was significantly associated with the level of evidence. Higher-quality orthodontic studies were more likely published in established orthodontic journals (likelihood ratio test P < .001).

Limitations: The identification and classification of predatory journals are challenging due to their covert nature.

Conclusions: The majority of orthodontic articles were published in non-orthodontic journals. In addition, approximately one in five orthodontic studies were published in presumed predatory journals or in journals of uncertain legitimacy. Studies with higher levels of evidence were more likely to be published in established orthodontic journals.