Dimensions relies on the unpaywall data set to flag articles as Open Access and for the full text button. If a publication is not included there, then a full text button is not shown.

In addition to the Unpaywall data, we tag publications as Gold OA if the journals they were published in are listed in the Directory of Open Access Journals (DOAJ) and their publication year is also the journal's first OA year or any year thereafter. OA status labeling based on DOAJ takes precedence over Unpaywall labeling.

Lastly, we maintain a list of fully Open Access journals to complement Unpaywall and DOAJ data, filling any gaps in their coverage. All publications from these journals are labeled as Gold OA by default, except when a journal appears on both our list and the DOAJ. In these instances, we prioritize the DOAJ logic, using the year of the first Open Access publication to identify Gold OA publications. Labeling based on this list takes precedence over Unpaywall labeling.

Definition of Open Access filters

All OA
A free version of the publication is available (publication is either Gold, Hybrid, Bronze or Green OA)
Gold
Publication is published in a fully open access journal (this includes all publications with a Gold OA status in Unpaywall and those on our own fully OA list of journals)
Hybrid
Publication freely available under an open licence in a paid-access journal (Unpaywall OA status = Hybrid)
Bronze
Publication freely available on publisher's website, but without an open licence (Unpaywall OA status = Bronze)
Green
Publication freely available in an OA repository (Unpaywall OA status = Green, or publication type in Dimensions = Preprint)
ClosedNo freely available version has been identified (publication is neither Gold, Hybrid, Bronze nor Green OA)