ABSTRACT
OBJECTIVES: This study evaluated knowledge structure and its effect factor by analysis of co-author and keyword networks in Korea's preventive medicine sector. METHODS: The data was extracted from 873 papers listed in the Journal of Preventive Medicine and Public Health, and was transformed into a co-author and keyword matrix where the existence of a 'link' was judged by impact factors calculated by the weight value of the role and rate of author participation. Research achievement was dependent upon the author's status and networking index, as analyzed by neighborhood degree, multidimensional scaling, correspondence analysis, and multiple regression. RESULTS: Co-author networks developed as randomness network in the center of a few high-productivity researchers. In particular, closeness centrality was more developed than degree centrality. Also, power law distribution was discovered in impact factor and research productivity by college affiliation. In multiple regression, the effect of the author's role was significant in both the impact factor calculated by the participatory rate and the number of listed articles. However, the number of listed articles varied by sex. CONCLSIONS: This study shows that the small world phenomenon exists in co-author and keyword networks in a journal, as in citation networks. However, the differentiation of knowledge structure in the field of preventive medicine was relatively restricted by specialization.
Subject(s)
Humans , Authorship , Community Networks/organization & administration , Korea/epidemiology , Periodicals as Topic , Preventive MedicineABSTRACT
OBJECTIVES: There are very few researches on North Korea's academic activities. Furthermore, it is doubtful that the available data are reliable. This study investigated research activities and knowledge structure in the field of Preventive Medicine in North Korea with a network analysis using co-authors and keywords. METHODS: The data was composed of the North Korean Journal of preventive medicine ranged from Vol. 1 of 1997 to Vol. 4 of 2006. It was the matrix of 1,172 articles by 1,567 co-authors. We applied R procedure for keywords abstraction, and then sought for the outcome of network forms by spring-KK and shrinking network. RESULTS: To comprehend the whole networks explicitly demonstrated that the academic activities in North Korea's preventive medicine were predisposed to centralization as similar as South Korea's, but on the other aspect they were prone to one-off intermittent segmentation. The principal co-author networks were formulated around some outstanding medical universities seemingly in addition to possible intervention by major researchers. The knowledge structure of network was based on experimentation judging from keywords such as drug, immunity, virus detection, infection, bacteria, anti-inflammation, etc. CONCLUSIONS: Though North Korea is a socialist regime, there were network of academic activities, which were deemed the existence of inducive mechanism affordable for free research. Article keywords has laid greater emphasis on experiment-based bacterial detection, sustainable immune system and prevention of infection. The kind of trend was a consistent characteristic in preventive medicine of North Korea having close correlation with Koryo medical science.