A measure of local uniqueness to identify linchpins in a social network with node attributes

Abstract

Network centrality measures assign importance to influential or key nodes in a network based on the topological structure of the underlying adjacency matrix. In this work, we define the importance of a node in a network as being dependent on whether it is the only one of its kind among its neighbors’ ties. We introduce linchpin score, a measure of local uniqueness used to identify important nodes by assessing both network structure and a node attribute. We explore linchpin score by attribute type and examine relationships between linchpin score and other established network centrality measures (degree, betweenness, closeness, and eigenvector centrality). To assess the utility of this measure in a real-world application, we measured the linchpin score of physicians in patient-sharing networks to identify and characterize important physicians based on being locally unique for their specialty. We hypothesized that linchpin score would identify indispensable physicians who would not be easily replaced by another physician of their specialty type if they were to be removed from the network. We explored differences in rural and urban physicians by linchpin score compared with other network centrality measures in patient-sharing networks representing the 306 hospital referral regions in the United States. We show that linchpin score is uniquely able to make the distinction that rural specialists, but not rural general practitioners, are indispensable for rural patient care. Linchpin score reveals a novel aspect of network importance that can provide important insight into the vulnerability of health care provider networks. More broadly, applications of linchpin score may be relevant for the analysis of social networks where interdisciplinary collaboration is important.

Systematic annotation of a complete adult maleDrosophilanerve cord connectome reveals principles of functional organisation

“…A node X belonging to community Y has a score of n if, by removing X from the graph, Y is directly connected to n less communities. It is related to, but not identical to, the linchpin measure in (Nemesure et al, 2021).…”

Telehealth Use Following COVID-19 Within Patient-Sharing Physician Networks at a Rural Comprehensive Cancer Center: Cross-sectional Analysis

“…Patient-sharing relationships have been shown to capture self-reported professional relationships between physicians [ 14 ]. Patient-sharing networks have provided insight into informal integration between primary care and specialists, coordination among patient care teams, and locally unique linchpin physicians [ 15 - 17 ]. There is significant potential for patient-sharing networks to measure the impact of new policies and innovative care delivery models on the way in which physicians work together to deliver health care to their patients.…”

Use of a Novel Network-Based Linchpin Score to Characterize Accessibility to the Oncology Physician Workforce in the United States

“…Herein, we describe a network-based physician linchpin score to capture how vital a physician is for bringing their specialtyspecific expertise to their peers. 9 Taking its name from a small but important metal pin used to prevent a wheel from sliding off its axle, physicians are characterized as a linchpin when fewer of their peers are connected to other physicians of the same specialty as the focal physician. Because they are locally unique for their specialty, we posit that their networks would be particularly vulnerable to their removal from the network (eg, through relocation or retirement).…”

“…The importance of relationships, particularly those involving multiple specialties and spanning practices, provides a strong rationale for leveraging network analysis to enhance the measurement of the oncology workforce. Herein, we describe a network-based physician linchpin score to capture how vital a physician is for bringing their specialty-specific expertise to their peers . Taking its name from a small but important metal pin used to prevent a wheel from sliding off its axle, physicians are characterized as a linchpin when fewer of their peers are connected to other physicians of the same specialty as the focal physician.…”