Which database with article processing charges should be used?

Although several databases collect article processing charges for open access, their data collection methods differ. This study investigated the characteristics of three databases compiling article processing charges—price lists on publishers’ official websites, Directory of Open Access Journals, and OpenAPC—for open access journals published by Elsevier, Springer Nature, and Wiley. Although many article processing charges listed on Directory of Open Access Journals are identical to those listed on price lists for 2023, several article processing charges on the Directory are not updated. Based on transformative agreements and other contracts, some publishers charge authors and research institutions article processing charges that differ from list prices presented on publishers’ websites. Considering this circumstance, OpenAPC compiles the article processing charges paid for individual articles. Using OpenAPC data, one can estimate the expenditures for each research institution. However, the number of journals listed on OpenAPC is considerably smaller than that listed on price lists. Moreover, journals on OpenAPC have higher list prices and citation scores and publish more articles than non-OpenAPC journals. Thus, journals on OpenAPC are not representative of open access journals in general. Nevertheless, the correlation between list prices and actual article processing charges paid indicates a strong positive relationship, implying that even if empirical studies on article processing charges use different databases, the database chosen might not significantly influence their conclusions.