Journals in Beall's list perform as a group less well than other open access journals indexed in Scopus but reveal large differences among publishers

The list of potential, possible or probable predatory scholarly open access (OA) publishers compiled by Jeffrey Beall was examined to determine the effect of their inclusion upon authors, and a possible bias against OA journals. Manually collected data from the publication archives of a sample of 250 journals from Beall publishers reveals a strong tendency towards a decline in their article output during 2012–2020. A comparison of the subset of 506 Beall journals indexed in Scopus with a benchmark set of other OA journals in Scopus with similar characteristics shows that Beall journals reveal as a group a strong decline in citation impact over the years, and reached an impact level far below that of their benchmarks. The Beall list of publishers was found to be heterogeneous in terms of bibliometric indicators but to be clearly differentiated from OA journals not included in the list. The same bibliometric comparison against comparable non-OA journals reveal similar, but less marked, differences in citation and publication growth.peerReviewe