Table 2 Definition of access categories at the paper level
Category | Definition | Article processing fees | Subscription fees | Embargo |
|---|---|---|---|---|
Gold OA article (no APC) | Article published in gold OA journal website when published; instantly available on journal website when published | No | No | No |
Gold OA article (with APC) | Article published in gold OA journal; instantly available on journal website when published | Yes | No | No |
Delayed OA article | Free article published in delayed OA or subscription journal with delayed OA option | No | Yes | Yes |
Hybrid article | Free article published in a subscription journal | Yes | Yes | No |
Green OA article | Articles in subscription or hybrid journals which have been self-archived by the author or affiliated institution to provide free access | No | No | No |
Other free access | Free article in subscription journal or journal for which the status is unknown | Unknown | Sometimes | Sometimes |
Toll access | Article that can only be accessed through a subscription or pay-per-view model and has not been self-archived | No | Yes | Yes |
Paper status unknown | Article for which the access status could not be determined | Unknown | Unknown | Unknown |