title: Unfolding similarity in interphysician networks: the impact of institutional and professional homophily.
abstract: BACKGROUND
  Modern healthcare is characterized by high complexity due to the proliferation of specialties, professional roles, and priorities within organizations. To perform clinical interventions, knowledge distributed across units, directorates and individuals needs to be integrated. Formal and/or informal mechanisms may be used to coordinate knowledge and tasks within organizations. Although the literature has recently considered the role of physicians' professional networks in the diffusion of knowledge, several concerns remain about the mechanisms through which these networks emerge within healthcare organizations. The aim of the present paper is to explore the impact of institutional and professional homophilies on the formation of interphysician professional networks.
  
  
  METHODS
  We collected data on a community of around 300 physicians working at a local health authority within the Italian National Health Service. We employed multiple regression quadratic assignment procedures to explore the extent to which institutional and professional homophilies influence the formation of interphysician networks.
  
  
  RESULTS
  We found that both institutional and professional homophilies matter in explaining interphysician networks. Physicians who had similar fields of interest or belonged to the same organizational structure were more likely to establish professional relationships. In addition, professional homophily was more relevant than institutional affiliation in explaining collaborative ties.
  
  
  CONCLUSIONS
  Our findings have organizational implications and provide useful information for managers who are responsible for undertaking organizational restructuring. Healthcare executives and administrators may want to consider the structure of advice networks while adopting new organizational structures.
authors.affiliation: Department of Public Health and ALTEMS (Graduate School of Health Economics and Management), Catholic University of the Sacred Heart, Largo F. Vito 1, 00168, Rome, Italy. dmascia@rm.unicatt.it.
authors.forename: Daniele
authors.initials: D
authors.lastname: Mascia
authors.affiliation: Department of Economic Studies, G. d'Annunzio University, Viale Pindaro 42, 65127, Pescara, Italy. f.divincenzo@unich.it.
authors.forename: Fausto
authors.initials: F
authors.lastname: Di Vincenzo
authors.affiliation: Department of Economics and Management and ALTEMS (Graduate School of Health Economics and Management), Catholic University of the Sacred Heart, Largo F. Vito 1, 00168, Rome, Italy. valentina.iacopino@rm.unicatt.it.
authors.forename: Valentina
authors.initials: V
authors.lastname: Iacopino
authors.affiliation: Department of Public Health, University of Bologna, Via San Giacomo 12, 40126, Bologna, Italy. mariapia.fantini@unibo.it.
authors.forename: Maria Pia
authors.initials: MP
authors.lastname: Fantini
authors.affiliation: Department of Economics and Management and ALTEMS (Graduate School of Health Economics and Management), Catholic University of the Sacred Heart, Largo F. Vito 1, 00168, Rome, Italy. acicchetti@rm.unicatt.it.
authors.forename: Americo
authors.initials: A
authors.lastname: Cicchetti
mesh_terms: D001291:Attitude of Health Personnel; D003299:Cooperative Behavior; D003430:Cross-Sectional Studies; D005260:Female; D006268:Health Facilities; D006801:Humans; D007400:Interprofessional Relations; D007558:Italy; D008297:Male; D009313:National Health Programs; D010820:Physicians / Q000523:psychology*; D024382:Professional Role; D060756:Social Networking; D011795:Surveys and Questionnaires