Publishing trends of journals with manuscripts in PubMed Central: changes from 2008–2009 to 2015–2016

OBJECTIVE: The National Institutes of Health (NIH) public access policy mandates that all articles containing NIH-funded research must be deposited into PubMed Central (PMC). The aim of this study was to assess publishing trends of journals that were not selected for the National Library of Medicine (NLM) collection but contain NIH-funded articles submitted to PMC in compliance with the public access policy. In addition, the authors investigated the degree to which NIH-funded research is published in journals that NLM does not collect due to concerns with the publishers. METHODS: We analyzed bibliographic data from the NIH Manuscript Submission system for journals that were not selected for the NLM collection from August 2015 to August 2016. Publications (n=738) were analyzed by language, publishing country, publishing format, and subject, and the results were compared to a similar study of 2008–2009 data. In addition, publications were analyzed by whether their publishers are collected by NLM, as determined by transparency and adherence to publishing best practices. RESULTS: Only a few differences were found between the studies. Most notably, while both studies revealed that most journals were not selected for the NLM collection because they were out of scope (i.e., not biomedical), we noted an increase in 2015–2016 in biomedical journals containing NIH-funded articles that were not added to the collection due to concerns with the publishers. CONCLUSIONS: While the current number of NIH-funded manuscripts being published by publishers that are not collected by NLM remains quite small, we noted a substantial increase between 2008–2009 and 2015–2016.