COVID Project Strengths and Limits

CEC-UW Strengths

  • Very Large and Varied Population:
    • Estimated 370,000 COVID patients
    • Estimated 70,000 hospitalized patients (who have extensive EHR data)
    • 21 different health systems from across the nation with diverse populations
  • The Potential of Longitudinal Data:
    • Because each patient maintains a unique identifier and health data are updated monthly through 2020, we can:
      • Evaluate the frequency and types of re-treatment (inpatient or outpatient) for both COVID and non-COVID illnesses.
      • Assess the impact of the evolution of the disease and its treatments on outcomes (e.g., changes in death rates within and across health systems).
  • Extensive Array of Data Elements:
    • This provides the capacity to examine many discrete EHR data elements that may influence outcomes.
  • Monthly Data Pulls Retrospective to February 1, 2020:
    • This allows for the addition and refinement of data elements over time to:
      • Add data elements of interest over time (e.g., Remdesivir, neurologic symptoms).
      • Improve accuracy of data elements collected (e.g., COVID diagnostic criteria, death definition).

CEC-UW Limitations

  • Data transferCOVID Cases Only: Since the cohort is limited to individuals diagnosed with COVID, we’re unable to examine risk of developing COVID.
  • Discrete Data Elements Only: The data pulled is almost exclusively limited to discrete EHR data elements. It doesn’t include data from text fields within the EHR.
  • Missing Data: For many EHR data elements (e.g., vaping), a large proportion of patients have no data reported.
  • De-identified HIPPA-Compliant Data. Limitations include:
    • Dates of treatments.
    • Geographic location below the state level.
  • Harmonizing EHR Data Across Health Systems.
  • Patient Data Limited to Health System Where COVID Was Diagnosed.

CEC-UW Essentials

370,000 COVID patients

21 health systems

Harmonized EHR Data