Abstract: Introduction: Conversely to diamond open access, gold open access is associated with article processing charges (APCs), which may represent an important burden in research budgets. The aim of this study was to identify the level of dependence of Portuguese scholarly publications from the five major APC-based publishers: BMC, Frontiers, Hindawi, MDPI, and PLoS.
Methods: Documents published from 2000 to 2022, containing an author’s address (AD field) including the word “Portugal” and assigned to any of the five publishers (PUBL field) were extracted from the Web of Science (WoS) Core Collection on April 21, 2023. Only documents catalogued as article, review, editorial material, or letter as Document Type were considered. Institutions names were obtained from the Portuguese General Directorate of Higher Education. Dependency was defined as the proportion of documents published in APC-journals from the total documents with a Portuguese author in the WoS.
Results: During the 23 years of study, 30,691 documents were published by Portuguese authors in the 663 journals published by these publishers: 3,202 documents in 210 BMC journals, 4,252 in 66 Frontiers journals, 1,448 in 172 Hindawi journals, 19,043 in 209 MDPI journals, and 2,746 in 6 PLoS journals. Overall, this production represents 7.5% of all the documents indexed in the Web of Science with Portugues authors, increasing from 0% in 2000 but reaching 24% in 2022. Significant different APC-dependency in 2022 was found between types of institutions with 30.4% (SD 6.5) in universities, 35.9% (SD 12.5) in polytechnic institutes, and 13.7% (SD 7.2) in other institutions.
Conclusion: An increasingly growing proportion of Portuguese authored documents are being published in the five biggest APC-based publishers, reaching almost 25% of all the documents published in 2022. APCs paid in 2022 overcomes the amount devoted to doctoral grants in Portugal. To reduce the burden of these publishing practices, funding bodies and higher education institutions should consider reinforcing the diamond open access publishing system.