Analyzing DocGraph in Gephi

Janos G. Hajagos Stony Brook School of Medicine

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NYC Open Data Meetup June 24, 2013

DocGraph

• Based on FOIA request to CMS by Fred Trotter • Medicare providers (more than doctors) • CY 2011 date of service • Share 10 or more patients in a 30 day forward

window • Initial access restricted to MedStartr funders

but as of June 2013 open access

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Geographic Visualization

http://isurfsoftware.com/blog/2012/12/13/visualizing-geographic-connections-between-us-doctors/

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DocGraph by the numbers

• Directed graph • Average total degree 52.8 • 940,492 providers (graph nodes/vertices) • 49,685,810 shared edges

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DocGraph Data

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NPPES

• National Plan and Provider Enumeration System

• Source of NPI (National Provider Identifier) • Information is entered and updated by

provider • CSV file with 314 columns • MySQL load script generated by Python script

to normalize database

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Selecting a sub-graph

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Core nodes

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Leaf nodes

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Core-to-core edges

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Core-to-leaf edges

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Leaf-to-leaf edges

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Generating GraphML

• XML based file format for graphs • Readable by a large number of tools

– Gephi – Mathematica – igraph (R)

• NetworkX Python library for graphs can easily export to GraphML

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Gephi

Subset defined from 2 Brooklyn zip codes (11215 - Park Slope & 11212 - Brownsville)

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Links

http://strata.oreilly.com/2012/11/docgraph-open-social-doctor-data.html (information) https://github.com/jhajagos/DocGraph (code) https://github.com/ftrotter/DocGraph (data) https://groups.google.com/forum/#!forum/docgraph (mailing list) http://bit.ly/1459NXn (sample Brooklyn GraphML file) http://strataconf.com/rx2013/public/schedule/detail/29840 (StrataRX workshop with Fred Trotter)

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