Appendix 1 — a description of the Chinese national databases
CNKI
The album of medical and health included in Chinese National Knowledge Infrastructure database (CNKI) provided the information about the medicine, pharmacy, Chinese medicine, health, health care, biology and so on. There are more than 700 kinds of Medical health core full textperiodicals, and 1800 related journals. The following database ordered：
Chinese National Knowledge Infrastructure database (CNKI)
●Key project of national information construction
●Dedicated to the mass digitalization of China knowledge resources, as well as creating a platform for global dissemination and value-added services
●Started and first launched in June 1999 by TsinghuaUniversity and Tsinghua Tongfang Holding Group
●Supported by the Education Ministry, the Science and Technology Ministry, the Propaganda Ministry and the General Administration of Press and Publications
●Self-developed cutting-edge Chinese digital library technologies and grid resources sharing platform
●Built the most comprehensive system of academic knowledge resourcesin China– the China Integrated Knowledge Resources Database
●China Knowledge Resource Integrated Database：
China Academic Journals Full-text Database: 1915 onwards; 44,994,691 records in total
China Doctoral Dissertations Full-text Database: 1984 onwards; 204,066 records in total
China Masters' Theses Full-text Database: 1984 onwards; 1,742,193 records in total
China Proceedings of Conference Full-text Database: 1953 onwards, 1,526,603 records in total
China Core Newspapers Full-text Database: 2000 onwards, 11,714,583 records in total
China Yearbooks Full-text Database: 1912 onwards, 17,632,827 records in total
●Single Database Search:
Century Journals Project: 1915-1993; 5,153,214 records in total
Century Journals Social Sciences: 1915-1993; 196,419 records in total
China Monographic Series Full-text Database: 1979 onwards; 122,812 records in total
China Reference Works Online: 1973 onwards; more than 4,000 titles
China Statistical Yearbooks Full-text Database: 1949 onwards; 847 titles
China Legal Knowledge Integrated Database: 1949 onwards; 2,053,231 records
China Culture Journals Database: 1979 onwards; 2,462,382 records
China Liberal Arts Journals Database: 1979 onwards; 1,567,448 records
China Patent Full-text Database: 1985 onwards; 7,248,874 records
Chinese Standard Full-text Database: 1950 onwards; 38,788 records
China English Journals Full-text Database: 1915 onwards
English Index of China Journals Database: 2007 onwards
China Journals Deep-Indexing Database: 1979 onwards
Wanfang
Wanfang Data, an affiliate of the Chinese Ministry of Science & Technology, provides access to a wide range of database resources, serving as a gateway to Chinese culture, medicine, business, science, engineering, etc. Wanfang Data currently contains over 12,000 volumes of the core journals in China, provides approximately 2,300 full-text journal titles published in China and over 3,000 quotations from 1986 onwards.There are 3 versions (full-text, abstract and quotation) and 8 albums (Social science, natural science, engineering, agricultural science, medicine and health care, economic management, education science,library and information).
Chongqing VIP
Chongqing VIP Information Co., Ltd., formerly known as DatabaseResearchCenter under Chongqing Branch of Institute of Scientific & Technical Information of China (CB-ISTIC), is China's first Chinese journal database research institution. The Database Research Center of CB-ISTIC, established in 1989, served as the pioneer of the database industry in China. In the same year, this ResearchCenter independently developed and launched “CB ISTIC/CEPC Periodicals China Base”, which is not only China's first Chinese Journal Literature database, but also China's largest self-built Chinese literature database.
CBM
The Chinese biomedical literature database (CBMdisc)contains more than 1,600 journals including 4.90 million articles starting from 1978. It collects data includingthe simple information of the bibliography and the abstract covering quotations and so on.