National COVID Cohort Collaborative Frequently Asked Questions

Read answers to frequently asked questions about the National COVID Cohort Collaborative (N3C).

1. What is the National COVID Cohort Collaborative, or the N3C?

The N3C represents a collaborative vision for a national data resource that will turn data into the knowledge that is urgently needed to address the COVID-19 pandemic. The N3C will systematically and regularly collect data derived from electronic health records (EHRs) from different institutions and harmonize these data in a centralized resource made available for collaborative research.

2. Why is the N3C needed?

The N3C will make data available for the clinical and research community to use for studying COVID-19 and for identifying potential treatments as the pandemic continues to evolve. The N3C strives to coordinate and harmonize needed data derived from EHRs to support efforts in understanding how best to direct research efforts and care of COVID-19 patients. Rapid collection of clinical, laboratory and diagnostic data from hospitals and health care plans at the peak of the pandemic and as the pandemic evolves will contribute to an understanding of the disease, informing the design of clinical studies and trials, facilitating the identification of effective interventions and informing care decisions. The goal is to aggregate and harmonize enough clinical data on a recurring basis from COVID-19 tested patients, or those with related symptoms, to support data analytics and statistics that require a large amount of data. The N3C aims to include clinical data for patients who represent diverse (e.g., geographic, socioeconomic, racial/ethnic, age, those with underlying medical conditions) populations.

3. What are the goals of the N3C?

The goals of the N3C are: 1) to create a robust data pipeline to harmonize EHR data into a common data model; 2) to make it fast and easy for the clinical and research community to access a wealth of COVID-19 clinical data and use it to research COVID-19 and identify effective interventions as the pandemic continues to evolve; 3) to establish a resource for the next 5 years to understand long-term health impact of COVID-19; and 4) to create a state-of-the-art analytics platform to enable novel analyses that will serve to address COVID-19 as well as to demonstrate that this collaborative analytics approach could be invaluable for addressing other diseases in the future.

4. Who is the N3C?

The N3C is a partnership among the NCATS-supported Clinical and Translational Science Awards (CTSA) Program hubs and the National Center for Data to Health (CD2H), with overall stewardship by NCATS. Collaborators will contribute and use COVID-19 clinical data to answer critical research questions to address the pandemic.

5. Where can interested parties/institutions learn more about the N3C?

Additional details about the program are available on the National Center for Data to Health’s N3C website.

For CTSA Program investigators: Watch the presentation NCATS Director Christopher P. Austin, M.D., gave to the CTSA Program consortium on May 8, 2020 or download the slides.

6. Who can join, and why should they join?

Partnerships are welcome. Data provision and data access are open to all entities that execute the NCATS Data Transfer Agreement (DTA) and NCATS Data Use Agreement (DUA), respectively. You do not have to contribute data to be able to access the data.

Joining the N3C provides an opportunity to contribute to the national response to the pandemic. Provision of COVID-19 clinical data will allow researchers to better understand the presentation and course of the disease in different populations, including potential health impact over time, to identify best practices for patient care, and to design and prioritize clinical studies and trials.

7. What is expected of a participating institution?

NCATS has established a COVID-19 DTA that provides terms and conditions for data transfer and outlines the general terms of data use. Institutions sign the DTA, then work with NCATS to transfer a “Limited Data Set” relevant to COVID-19 in the institution’s preferred common data model (derived from electronic health records) to a centralized, secure, cloud-based enclave on a recurring basis.

Note that if a CTSA Program hub has multiple partners, it is likely that each institution will be required to sign separate DTAs, unless the hub can demonstrate that it has the legal authority to use data of the partner institution.

8. What fields are the N3C requesting as part of the Limited Data Set?

Read the OMOP Version 5.3.1 Common Data Specifications that are being requested.

9. When can data transfer start?

Because of the national urgency and the need to make this resource available, NCATS encourages interested parties to contact its Office of Strategic Alliances at for instructions on executing the DTA. The goal is to start acquiring clinical data immediately and show proof of principle for answering important COVID-19 research and health care questions as soon as possible.

10. Who is the point of contact regarding data transfer or technical questions about the platform?

Please email specific questions to

11. How does NCATS plan to ensure data security and privacy?

NCATS is taking multiple precautions for security and privacy to keep these data safe within its protected cloud infrastructure, including role-based access controls and full system log entries; granular host and network level logging; robust end-to-end encryption of all traffic via SSL/TLS, authentication, white-listing mechanisms; and comprehensive auditing of all data processing and access within the cloud platform. The Palantir platform in use resides in Amazon Web Services GovCloud and is FedRAMP authorized at a Moderate impact level. The DUA specifies that N3C data will be used only for clinical and translational research and public health surveillance of COVID-19. The Limited Data Set will contain demographics including the zip code of the health care service provider and dates of service. Specific institutions will not be identified, though it might be possible to infer institutional identity. Disclosure of this information will be prohibited. Data use will be governed by an oversight committee. Users must be “approved” and can only analyze data within the platform; data cannot be removed or downloaded.

12. How long until the data can be used?

The goal is to start acquiring clinical data immediately and show proof of principle for answering important COVID-19 research and health care questions as soon as possible. Data availability is dependent upon when data are deposited into the platform and the execution of a DUA, which is currently under development.

13. Will the data set include clinical information about various populations (e.g., children, the elderly, patients who represent racial and ethnic minority populations)?

Yes, the N3C aims to be as inclusive as possible.

14. What funding opportunities are available to support researchers’ participation?

  1. CTSA hubs and other entities can contribute data as soon as a DTA has been executed.
  2. If needed, limited funds are available to current Clinical and Translational Science Award (CTSA) UL1s under NOT-TR-20-028 Emergency NOSI to support personnel and resources for data transfer (awards anticipated to be $50,000 to $100,000 Total Costs).
    1. NOT-TR-20-028 includes rolling submission of applications; however, as the end of the fiscal year approaches, NCATS must defer some applications for FY21 funding considerations.
    2. The number of awards is contingent upon NIH appropriations and the submission of a sufficient number of meritorious applications.
    3. Neither a DTA nor DUA need to be in place before submission of an application in response to NOT-TR-20-028; awards will be issued with restrictive terms and conditions that prohibit use of funds for these activities until DTA and/or DUA is executed.

15. Who can address any additional questions?

Please email questions about the N3C to