Percentages of open access publications in 2016 and 2017

The VSNU agreed with the Ministry of Education, Culture and Science to monitor open access publications. The VSNU agreed to divide the registration into ‘gold’, ‘hybrid’ and ‘green’. Together with experts from the universities, the VSNU developed a definition framework for monitoring open access publications, which is applied by every university.
In 2017 and 2018, the universities established the proportion of articles published in 2016 and 2017 that were open access. These percentages should be regarded as an initial monitoring of open access publications. There are still some inconsistencies in terms of validity and reliability amongst the measurements used. 
Distinction between ‘gold’, ‘hybrid’ and ‘green’
An article must be accessible to everyone freely and permanently in order to be open access. This applies when the article is published in an open access journal: ‘gold’. A second option is to publish an open article in a paid subscription journal: ‘hybrid’. The ‘green’ route refers to making the article available through what is known as a ‘trusted repository’ (a digital archive depot, for example belonging to a university). In order to determine which journals are available open access, we followed the Directory of Open Access Journals (DOAJ). This is an online register of open access, peer-reviewed journals. 
In short, we divided open access articles into three categories:
⦁    ‘Gold’: Open articles in open access (DOAJ) journals;
⦁    ‘Hybrid’: Open articles in paid journals and open articles in open journals that are not listed in the DOAJ;
⦁    ‘Green’: Articles that are only available open access because they are offered through a ‘trusted repository’.
The first category comprises every article published in a DOAJ journal during the measurement years. The remaining articles were examined to determine whether they are available open access on the publisher’s platform even though they were not published in an open access journal. The majority are hybrid publications. This leaves a proportion of the peer-reviewed articles. The remaining peer-reviewed articles were examined to determine whether they can be found in a ‘trusted repository’. In other words, the ‘trusted repositories’ were not searched for articles from DOAJ journals and hybrid articles. After all, if the universities were to do so, the total percentage could (theoretically) exceed 100% open access. 
Results of monitoring open access publications in 2016 and 2017 according to definition framework
The figures show that 50% (nearly 28,000 articles) of the peer-reviewed articles from 2017 from the 14 Dutch universities are available open access. All articles published during the measurement year with one or more authors affiliated with a Dutch university were examined by the institutions (nearly 56,000 articles). The study only looked at articles that 1) are aimed at a scientific audience; 2) were peer reviewed; and 3) were published in an academic journal. The table below shows the percentages by category. 


Table 1: Percentages OA publications 2016 and 2017 Dutch universities by category