Open access papers: their growth over time and from different countries, and their citations

The Web of Science now records the Open Access (OA) status of papers that it covers. Papers with OA = yes have grown rapidly since 2000 and the proportion has reached 18% of the total in biomedical research but only 4% in chemistry. Countries also vary greatly in their preference for publishing in OA journals: Brazil tops the list in four fields but not in physics where the Ukraine and Russia use OA the most among the 30 top publishers in 2015. Contrary to popular belief that OA papers would receive more citations, this appears not to be true, probably because the top-cited journals are not OA, some OA journals may have lower peer-review and editorial standards, and because in some countries (e.g., Brazil, Spain) many OA journals are not in English. However, there is some evidence that OA papers may be attracting more citations from researchers in lower-middle income and low-income countries.