This code system http://terminology.hl7.org/CodeSystem/variable-role defines the following codes:
\n \n \n \n \n \n Code\n \n | \n \n \n \n Display\n \n | \n \n \n \n Definition\n \n | \n \n
\n \n \n \n population\n \n \n \n | \n \n population | \n \n variable represents a population. | \n \n
\n \n \n \n subpopulation\n \n \n \n | \n \n subpopulation | \n \n variable represents a subpopulation. | \n \n
\n \n \n \n exposure\n \n \n \n | \n \n exposure | \n \n variable represents an exposure. | \n \n
\n \n \n \n referenceExposure\n \n \n \n | \n \n reference exposure | \n \n variable represents a reference exposure. | \n \n
\n \n \n \n measuredVariable\n \n \n \n | \n \n measured variable | \n \n variable represents a measured variable. | \n \n
\n \n \n \n confounder\n \n \n \n | \n \n confounder | \n \n variable represents a confounder. | \n \n
\n \n