| Code | Display | Definition |
| population | population | variable represents a population. |
| subpopulation | subpopulation | variable represents a subpopulation. |
| exposure | exposure | variable represents an exposure. |
| referenceExposure | reference exposure | variable represents a reference exposure. |
| measuredVariable | measured variable | variable represents a measured variable. |
| confounder | confounder | variable represents a confounder. |
| measuredVariableA | measured variable A | variable represents a first of two measured variables to be used in a measured variable that is a mathematical operation of two measured variables. |
| measuredVariableB | measured variable B | variable represents a second of two measured variables to be used in a measured variable that is a mathematical operation of two measured variables. |
| measuredVariableAB | measured variable A to B | variable represents a result of a mathematical operation of two measured variables. |