When PLOS ONE debuted in 2006, its founders declared it would transform scientific publishing. It was the first multidisciplinary, large-volume, open-access journal that published technically sound science without consideration of novelty. Five years later, Peter Binfield, then its publisher, forecast that by 2016, 50% of all scientific papers would appear in 100 such “megajournals.”
Based in San Francisco, California, PLOS ONE grew to become the world's largest journal, publishing more than 30,000 papers at its height in 2013 and spawning more than a dozen imitators—but megajournals have fallen far short of Binfield's aims. From 2013 to 2018, PLOS ONE's output fell by 44%. Another megajournal, Scientific Reports, surpassed PLOS ONE in size in 2017 but saw its article count drop by 30% the next year, according to data in publisher Elsevier's Scopus database. Growth in new megajournals has not offset the declines. In 2018, PLOS ONE, Scientific Reports, and 11 smaller megajournals collectively published about 3% of the global papers total.
PLOS ONE and Scientific Reports have also slipped on other measures of performance. Publication speeds, a key early selling point, have fallen. And a study published in August showed that by certain citation-based measures, the journals' connection to science's cutting edge has frayed.
“Megajournal publishers clearly have yet to persuade many researchers that their approach adds significant value to the scholarly communications ecosystem,” information scientist Stephen Pinfield of the University of Sheffield in the United Kingdom and colleagues wrote in a July study in the Journal of Documentation.
But megajournals still occupy a unique and important niche in scientific publishing, some analysts say. Because their acceptance rate is high—about 50% of submitted manuscripts—and they don't insist on novelty, they allow authors to publish valuable findings, such as replication studies and negative results, that might otherwise face rejection by traditional selective journals. They remain relevant as an option for European authors whose funders plan to require that their papers be free to read on publication. And megajournals' publishing fees—$1595 per paper at PLOS ONE, for example—remain low compared with more selective open-access journals, such as Nature Communications and Science's open-access sister journal, Science Advances, which charges $4500. (Science's news department is editorially independent.)
Driving the fall in output is a decline in submissions. At Scientific Reports, authors submitted fewer manuscripts after a drop in its impact factor—a measure of citations per paper, says James Butcher, vice president for journals at its parent company, Nature Research in London. The metric, which many authors follow closely, usually declines when a journal expands rapidly, as Scientific Reports did until recently.
CREDITS: (GRAPHIC) J. BRAINARD/SCIENCE; (DATA) SCOPUS
Joerg Heber, PLOS ONE's editor-in-chief, says its decline in submissions stems from increasing competition from newer open-access journals: “We had a first-mover advantage, now gone.” Leaders of PLOS ONE and Scientific Reports say submissions are rising again. PLOS ONE has added new services to attract more authors, including publishing peer reviewers' comments.
Meanwhile, the megajournals have lost one source of their appeal: rapid publication. Early on, PLOS ONE and Scientific Reports published papers an average of 3 months after submission, compared with traditional journals' average of about 5 months. But by 2018, PLOS ONE's lag had risen to 6 months and Scientific Reports's to 5 months, according to a 2018 study in Online Information Review. Both Heber and Butcher blame the logistical difficulties of handling large volumes and say they have improved staffing and operations to shrink the lags.
Perhaps more worrying: As publishing volumes have declined, so have megajournals' connections to the frontiers of science, according to a study by Petr Heneberg of Charles University in Prague. It looked at how often papers in 11 megajournals cited recently published papers in each of three highly ranked selective journals—Nature, the Proceedings of the National Academy of Sciences, and Science. It also analyzed the converse: how often papers in the three selective journals cited papers in the megajournals. For PLOS ONE, both measures fell significantly between 2008 and 2016, approaching zero, Heneberg reported in the August issue of Scientometrics. Other megajournals' citations to the three elite journals also plummeted.
Heber says Heneberg's study is too narrow to be meaningful. For example, he says PLOS ONE has recently published more clinical research, a topic that doesn't often appear in the three highly rated journals.
Even while the founding megajournals have lost momentum, others that are more selective or specialized are thriving. Three discipline-focused megajournals have grown rapidly in recent years: Medicine, from the publisher Wolters Kluwer; BMJ Open; and IEEE Access. Broad open-access journals such as Nature Communications and Science Advances that do consider papers' novelty have also expanded, notes Cassidy Sugimoto of Indiana University in Bloomington, co-author of a forthcoming study of such journals. “To me, that doesn't show that megajournals are dying,” she says, but instead suggests their trailblazing has led to a greater diversity of useful publishing options.
