About the Chinese Academy of Sciences (CAS) Journal Ranking system
The first database of CAS Journal Ranking was launched in 2004 by the National Science Library of CAS and it has been updated annually in October. It aims to avoid the misunderstanding and incomparability of impact factors across different disciplines, and to demonstrate the impact of a journal within its own discipline.
CAS ranks journals based on their impact factor and data from the Journal Citation Reports with the application of Bradford’s Law. In short, SCI and SSCI journals are partitioned according to the 3-year-average impact factors in their disciplines and then assigned to a hierarchy of tiers. These tiers in the CAS system are not the same as the quartiles in the JCR ranking. Whereas the JCR ranking divides journal ranks into four quartiles (25% each), the CAS system ranks journals in a more hierarchical fashion: Tier 1 (ca. top 5%), Tier 2 (5% - 15%), Tier 3 (15% - 50%), and Tier 4 (ca. remaining 50%).
The major categories in the CAS system are determined by the characteristics of China's research and education system and Chinese researchers’ cognition. It has been updated and improved over the years. Currently, there are 13 main categories: Medicine, Biology, Agricultural and Forestry Sciences, Environmental Sciences and Ecology, Chemistry, Engineering, Mathematics, Physics, Geosciences, Astrophysics, Social Sciences, Management, and Multidisciplinary. Sub-categories in the CAS system are identical to those found in the JCR system.
How is the journal ranking system used in China?
There is no unified, national journal ranking system in China. Publication policies differ from one institute to another and are not even consistent across departments within an institute. Usually, the chosen ranking system would be decided by the Head of Department in consultation with its academic committee. The CAS Journal Ranking system has been the most popular one in China, but researchers also widely use the JCR rankings or the Nature Index.
The National Science Library of CAS claims that more than 300 universities and research institutes subscribe to the database of the CAS Journal Ranking system. This suggests that at least 10% of Chinese universities and research institutes are either adopting this system or consulting it in their considerations of internal policy.
For institutes without a journal ranking list, researchers have been allowed to publish at their own discretion and most often researchers select journals based on impact factor.
Is it possible to influence journal rankings?
As far as we know, no matter which ranking system an institute adopts or refers to, they still rely heavily on impact factor. Occasionally, other factors may sway the position of a journal such as: the
journal’s status or prestige in a community; the status of the Editors and their engagement with the community/university; ownership or affiliation status; etc. Notably, many institutes do not recognize ‘mega-journals’ as real publications in promotion and tenure evaluation. Newly launched journals or journals without impact factors are usually excluded from the journal rankings; for that reason, new titles struggle to receive submissions from China. However, if a new journal can show its potential for a good impact factor, Chinese authors will submit papers to that journal. Potential might be demonstrated in various ways, e.g., if the new journal is an extension of a recognized journal ‘brand’, such as the Advanced series; if the journal has particularly prestigious Editors and Editorial Board Members (especially renowned Chinese researchers); or if the journal is or affiliated with top institutes or organizations.
It might be helpful for editors to engage in outreach activities in an institute or build up good
relationships with key opinion leaders in a department to sway their opinion in favor of a journal. The best approach is to ensure that the journal meets the strict criteria (e.g. impact factor) when the journal rankings are updated, which normally happens once a year if it refers to the external ranking system (such as the CAS Journal Ranking).
This article is based on research by the Wiley China Publishing Team, who gathered information through personal experience and interactions with the Chinese research community. Additionally, a brief survey was carried out with numerous researchers in 37 different institutes, universities, and hospitals across several subject areas.