title: Study of co-authorship network of papers in the Journal of Research in Medical Sciences using social network analysis.
abstract: BACKGROUND
  Co-authorship is one of the most tangible forms of research collaboration. A co-authorship network is a social network in which the authors through participation in one or more publication through an indirect path have linked to each other. The present research using the social network analysis studied co-authorship network of 681 articles published in Journal of Research in Medical Sciences (JRMS) during 2008-2012.
  
  
  METHODS
  The study was carried out with the scientometrics approach and using co-authorship network analysis of authors. The topology of the co-authorship network of 681 published articles in JRMS between 2008 and 2012 was analyzed using macro-level metrics indicators of network analysis such as density, clustering coefficient, components and mean distance. In addition, in order to evaluate the performance of each authors and countries in the network, the micro-level indicators such as degree centrality, closeness centrality and betweenness centrality as well as productivity index were used. The UCINET and NetDraw softwares were used to draw and analyze the co-authorship network of the papers.
  
  
  RESULTS
  The assessment of the authors productivity in this journal showed that the first ranks were belonged to only five authors, respectively. Furthermore, analysis of the co-authorship of the authors in the network demonstrated that in the betweenness centrality index, three authors of them had the good position in the network. They can be considered as the network leaders able to control the flow of information in the network compared with the other members based on the shortest paths. On the other hand, the key role of the network according to the productivity and centrality indexes was belonged to Iran, Malaysia and United States of America.
  
  
  CONCLUSIONS
  Co-authorship network of JRMS has the characteristics of a small world network. In addition, the theory of 6° separation is valid in this network was also true.
authors.affiliation: Assistant Professor, Medical Librarianship and Information Science, Health Information Technology Research Center, Isfahan University of Medical Sciences, Isfahan, Iran.
authors.forename: Firoozeh
authors.initials: F
authors.lastname: Zare-Farashbandi
authors.affiliation: PhD Student, Department of Knowledge and Information Science, Shahid Chamran University, Ahwaz, Iran.
authors.forename: Ehsan
authors.initials: E
authors.lastname: Geraei
authors.affiliation: MSc. of Library and Information Science, Shahid Chamran University, Ahwaz, Iran.
authors.forename: Saba
authors.initials: S
authors.lastname: Siamaki
keywords: Centrality; Journal of Research in Medical Sciences; density; mean distance; social network analysis