- the individual’s past, present or future physical or mental health or condition,
- the provision of health care to the individual,
- the past, present, or future payment for the provision of health care to the individual
In the RADx Data Hub, data are harmonized, or re-labeled and re-coded, so data can be uniformly interpreted across multiple studies. There are three types of RADx variables, categorized by their level of harmonization across the various RADx programs: Core (Tier I) variables, (C)DCC Common (Tier II) Variables, and Non-harmonized (Tier III) variables.
RADx Core Variables: Variables intended to be shared across all RADx studies involving human subjects, regardless of the specific RADx program. They are defined in the RADx Global Codebook and have identifiers beginning with “nih_”. Core variables are also referred to as RADx Common Data Elements (CDEs) or Tier I variables.
RADx (C)DCC Common Variables are intended to be shared across a subset of studies within a specific RADx program/(C)DCC. As a result, RADx-rad, RADx Tech, and RADx-UP each have their own set of Common Variables, defined in their respective data dictionaries. These are known as Tier II variables or RADx-rad Common Variables, RADx Tech Common Variables, RADx-UP Common Variables, respectively.
Non-harmonized Variables: Variables that are not a RADx Core Variable or RADx Program Common Variable. These are typically unique to an individual study and referred to as a Tier III variable.