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Cross Network Directory Service

Enabling data partners to engage with and access multiple research networks.
  • Food and Drug Administration (FDA)
Start Date
  • 7/15/2015
  • Use of Enhanced Publically-Funded Data Systems for Research


STATUS: Completed Project 


The FDA developed and implemented a Cross Network Directory Service (CNDS) that addresses the stand alone nature of existing distributed research networks and barriers to working across these networks. A CNDS enables individual networks to become a community of interoperable networks, allowing end users to participate in and move around from network to network as research needs dictate. This product enhances network scalability and enables data partners to engage with multiple networks, by allowing them to decide their level of participation and their governance rules.


This project created an open source interoperable service that allows data partners to participate in multiple data research networks, query across the networks, and share analytic capabilities and knowledge across networks. The project was piloted across two existing networks: FDA’s Sentinel System and the National Patient‑Centered Clinical Research Network (PCORnet).

Project Objectives:

  • Identify the key functionalities and an overarching technical design for a CNDS.

  • Develop and test a detailed design for the CNDS with at least two existing distributed research networks.

  • Conduct additional analyses of the robustness of the CNDS and produce user materials.


  • The design phase of the project—which included identifying business and technical requirements, determining and describing key functionalities—was completed in 2016 and detailed in a Use Case Summary Report.

  • The CNDS software application was designed, built, released, and tested. In early 2018, the project team prepared the technical and user documentation for the CNDS.

  • Beta testing of the software application was performed by a Sentinel and a PCORnet data partner. In the first round of beta testing, the data partners successfully registered and entered their metadata. In the second and final round of testing, the data partners successfully completed a round trip through Discovery (search data sources) and Communication (send and receive queries). Further, data partners were not able to discover data that the other partner did not actively make available.




  • The project team published “Cross-Network Directory Service: Infrastructure to enable collaborations across distributed research networks” in Learning Health Systems. The publication is available here:


  • “Cross Network Directory Service: A Socio-technical Platform to Enable Meaningful Collaboration across Organizations” was presented as an oral presentation at the Health Care Systems Research Networks Conference in Minneapolis in April 2018.

  • A project poster entitled “Cross Network Directory Service: Enabling Meaningful Collaboration Across Organizations” was presented at the AMIA 2018 Informatics Summit in San Francisco in March 2018.


Below is a list of ASPE-funded PCORTF projects that are related to this project

Strengthening and Expanding the Community Health Applied Research Network (CHARN) Registry to Conduct Patient-Centered Outcomes Research (PCOR) - CHARN is a network of the Health Resources and Services Administration’s (HRSA) community health centers (CHCs) and universities that was established in 2010 to create an infrastructure for this safety-net community to carry out patient-centered outcomes research (PCOR), including observational and interventional studies among underserved populations, ultimately leading to improved patient care and outcomes. To realize the full potential of the CHARN infrastructure for information sharing and research, CHARN wanted to expand and enhance its data registries and to make its data available to non-CHARN researchers conducting PCOR.