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A quest for the structure of intra- and postoperative surgical team networks: does the small-world property evolve over time?

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Abstract

We examined the structure of intra- and postoperative case-collaboration networks among the surgical service providers in a quaternary-care academic medical center, using retrospective electronic medical record (EMR) data. We also analyzed the evolution of the network properties over time, as changes in nodes and edges can affect the network structure. We used de-identified intra- and postoperative data for adult patients, ages ≥ 21, who received nonambulatory/nonobstetric surgery at Shands at the University of Florida between June 1, 2011 and November 1, 2014. The intraoperative segment contained 30,245 surgical cases, and the postoperative segment considered 30,202 hospitalizations. Our results confirmed the existence of small-world structure in both intra- and postoperative surgical team networks. In addition, high network density was observed in the intraoperative segment and partially in postoperative one, representing the existence of cohesive clusters of providers. We also observed that the small-world property is exhibited more in the intraoperative compared to the postoperative network. Analyzing the temporal aspects of the networks revealed that the postoperative segment tends to lose its cohesiveness as time passes. Finally, we observed the small-world structure is negatively related to patients’ outcome in both intra- and postoperative networks whereas the relation between the outcome and network density is positive. Small changes in graph-theoretic properties of the intra- and postoperative networks cause changes in the intensity of the structural properties. However, due to the special characteristics of the examined networks (e.g., high interconnectivity, team oriented), the network is less likely to lose its structural properties unless the central hubs are removed. Our results highlight the importance of stability of personnel in key positions. This highlights the important role of the central players in the network that offers change leaders the opportunity to quantify and target those nodes as mediators of process change.

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Data Availability

Please refer to the article’s GitHub page (https://github.com/Ashdi13/SmallWorld) for the scripts as well as a sample synthetic dataset. The original data may be shared through the University of Florida, upon application and developing a business data use agreement that we would process in a standard fashion.

Notes

  1. Providers’ role-specific network structure analysis is out of the scope of this study as we wanted to analyze the structure of the intra- and postoperative networks, and their trends, at the global level. However, analyzing the network structure of different roles can be considered as a future research direction.

  2. The word “graph” was first used by Sylvester (1878).

  3. In this problem, a man has to cross all the seven bridges once and continuously. Euler represented the problem as a set of nodes and edges and proved that the problem has no solution!

  4. We started with two-mode networks to emphasize the creation process of the networks. This also highlights the distinction between the primary node set, i.e., the surgical service providers, as well as the common node set, i.e. the surgical cases, as the node set used in projecting a two-mode network to a one-mode network.

  5. Since we constructed undirected unweighted networks of the surgical service providers, \(\forall i,j; {w}_{ij}\)=1.

  6. We would like to thank the anonymous reviewer for raising this point.

  7. For more details on the scale-free network analysis, please refer to our paper on scale-free characteristics of surgical networks (Ebadi et al. 2016).

  8. A complete graph is an undirected graph in which every pair of distinct nodes is connected.

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Authors and Affiliations

  1. Department of Biomedical Engineering, University of Florida, Gainesville, FL, USA

    Ashkan Ebadi & Parisa Rashidi

  2. Department of Anesthesiology, University of Florida, Gainesville, FL, USA

    Patrick J. Tighe & Lei Zhang

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  1. Ashkan Ebadi
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  2. Patrick J. Tighe
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  4. Parisa Rashidi
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Contributions

Conceiving and designing the experiments: AE, PJT, PR. Performing the experiments: AE. Analyzing the data: AE. Data/materials: PJT, LZ. Writing of the manuscript: AE, PJT, LZ, PR.

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Correspondence to Ashkan Ebadi.

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The University of Florida Institutional Review Board (IRB) approved this study (IRB number 201400976). The data for this research were collected from the University of Florida’s Integrated Data Repository (IDR) after obtaining a confidentiality agreement from the IDR.

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Appendix

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Table 1 Complication ICD9-CM code set
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Ebadi, A., Tighe, P.J., Zhang, L. et al. A quest for the structure of intra- and postoperative surgical team networks: does the small-world property evolve over time?. Soc. Netw. Anal. Min. 9, 7 (2019). https://doi.org/10.1007/s13278-019-0550-5

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