This case-sensitive code system http://hl7.org/fhir/questionnaire-display-category defines the following codes:

Code	Display	Definition
instructions	Instructions	The display text provides guidance on how to populate or use a portion of the questionnaire (or the questionnaire as a whole).
security	Security	The display text provides guidance on how the information should be or will be handled from a security/confidentiality/access control perspective when completed
legal	legal	The display text indicates copyright, trademark, patent, regulations regarding completion, retention or use, or other legal text related to the item