Table 1.

Currently Available Data in the Danish COVID-19 Cohort

Type of Information	Variables	Source
Demographic data	Sex	The Danish Civil Person Registry
	Date of birth
	Dates of immigration/emigration
COVID-19 test	Sampling date	The Danish Microbiology Database
	Test result
	Test type
	Sample material
COVID-19 outcomes	Date of hospital admission	Direct reporting from the Danish regions to Statens Serum Institut
	Date of hospital discharge
	Date of intensive care unit admission
	Date of mechanical ventilation
	Date of renal replacement therapy
Medical conditions and procedures	Diagnosis code (ICD-10)	The Danish National Patient Registry
	Date of diagnosis
	Surgery code (NCSP)
	Date of surgery
	Other procedures, eg BFCA0: implantation of pacemaker.
	Date of procedure
Vital status	Date of death	The Danish Causes of Death Registry and the Danish Civil Person Registry
Drug use	Date of prescription fill	The Danish National Prescription Registry
	Drug dispensed (ATC codes)
	Pack size
	Number of packs
	Strength of tables
	Drug administration and formulation
Authorized health care worker	Health care authorization and profession	The Danish Register of Healthcare Professionals
Laboratory test results	Laboratory values for selected biochemical markers	Register of Laboratory Results for Research

Abbreviations: ICD-10, International Classification of Diseases version 10; NCSP, Nordic Classification of Surgical Procedures; ATC, Anatomical Therapeutic Chemical Classification System.