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The National COVID Cohort Collaborative (N3C) harnesses the infrastructure and expertise of partners, including Clinical and Translational Science Awards (CTSA) Program hubs, distributed clinical data networks (PCORnet, OHDSI, ACT/i2b2, TriNetX), and others.


The COVID-19 pandemic raises many difficult questions for clinicians, researchers and informaticians. Which drugs are the most viable candidates for a given patient? How can we efficiently and effectively assemble the right cohort for a trial? What social determinants impact course and outcome? How can we rapidly deploy clinical decision support tools when new knowledge is available every day?

The National COVID Cohort Collaborative (N3C) harnesses the infrastructure and expertise of partners, including Clinical and Translational Science Awards (CTSA) Program hubs, distributed clinical data networks (PCORnet, OHDSI, ACT/i2b2, TriNetX), and others. The mission of the N3C is to improve the efficiency and accessibility of analyses with COVID-19 clinical data, expand the ability to analyze and understand COVID, and demonstrate a novel approach for collaborative pandemic data sharing. The N3C is doing this by building a centralized, EHR-based limited data set of COVID-19 patients and controls in a secure analytic environment where tools and algorithms can be rapidly evaluated, and clinicians and researchers can ask complex clinical questions.

The work of the N3C is organized into four workstreams, including

  1. Data partnership and Governance
  2. Phenotype and Data acquisition
  3. Data ingestion and Harmonization
  4. Collaborative analytics

Emily Pfaff, MS, Administrative Director of the Informatics and Data Science (IDSci) service at the North Carolina Translational and Clinical Sciences (NC TraCS) Institute, leads the Phenotype and Data acquisition workstream. Through a consensus process they have developed a COVID-19 phenotype that will define the data pull that will populate the limited data set. This workstream will also create a “white glove” service to obtain data from each site by building easily adaptable scripts for each clinical data model and ingest data into a secure location, per approved institutional agreements.

Learn more about the National COVID Cohort Collaborative at covid.cd2h.org/N3C.