title: Professional and geographical network effects on healthcare information exchange growth: does proximity really matter?
abstract: OBJECTIVE
  We postulate that professional proximity due to common patients and geographical proximity among practice locations are significant factors influencing the adoption of health information exchange (HIE) services by healthcare providers. The objective of this study is to investigate the direct and indirect network effects of these drivers on HIE diffusion.
  
  
  METHODS
  Multi-dimensional scaling and clustering are first used to create different clusters of physicians based on their professional and geographical proximities. Extending the Bass diffusion model to capture direct and indirect network effects among groups, the growth of HIE among these clusters is modeled and studied. The network effects among the clusters are investigated using adoption data over a 3-year period for an HIE based in Western New York.
  
  
  METHODS
  HIE adoption parameters-external sources of influence as well as direct and indirect network coefficients-are estimated by the extended version of the Bass diffusion model.
  
  
  RESULTS
  Direct network effects caused by common patients among physicians are much more influential on HIE adoption as compared with previously investigated social contagion and external factors. Professional proximity due to common patients does influence adoption decisions; geographical proximity is also influential, but its effect is more on rural than urban physicians.
  
  
  CONCLUSIONS
  Flow of patients among different groups of physicians is a powerful factor in HIE adoption. Rather than merely following the market trend, physicians appear to be influenced by other physicians with whom they interact with and have common patients.
authors.affiliation: Department of Management Science and Systems, School of Management, University at Buffalo, The State University of New York, Buffalo, NY 14260, USA.
authors.forename: Niam
authors.initials: N
authors.lastname: Yaraghi
authors.affiliation: Department of Management Science and Systems, School of Management, University at Buffalo, The State University of New York, Buffalo, NY 14260, USA.
authors.forename: Anna Ye
authors.initials: AY
authors.lastname: Du
authors.affiliation: Department of Management Science and Systems, School of Management, University at Buffalo, The State University of New York, Buffalo, NY 14260, USA.
authors.forename: Raj
authors.initials: R
authors.lastname: Sharman
authors.affiliation: Department of Management Science and Systems, School of Management, University at Buffalo, The State University of New York, Buffalo, NY 14260, USA.
authors.forename: Ram D
authors.initials: RD
authors.lastname: Gopal
authors.affiliation: School of Business, University of Connecticut, Storrs, Connecticut 06269, USA.
authors.forename: R
authors.initials: R
authors.lastname: Ramesh
authors.affiliation: Department of Family Medicine, University at Buffalo, The State University of New York, Buffalo, NY 14203, USA UB Patient Safety Research Center, University at Buffalo, The State University of New York, Buffalo, NY 14203, USA.
authors.forename: Ranjit
authors.initials: R
authors.lastname: Singh
authors.affiliation: Department of Family Medicine, University at Buffalo, The State University of New York, Buffalo, NY 14203, USA UB Patient Safety Research Center, University at Buffalo, The State University of New York, Buffalo, NY 14203, USA.
authors.forename: Gurdev
authors.initials: G
authors.lastname: Singh
mesh_terms: D003195:Computer Communication Networks; D057286:Electronic Health Records / Q000458:organization & administration*; D062306:Geography, Medical; D006801:Humans; D033181:Information Dissemination; D008498:Medical Record Linkage
keywords: Diffusion of Innovation; Health Information Exchange; Multi-sided platform; Network effects