Which FHIR resource is used for handling concepts not yet defined in FHIR, narrative-only resources that don't map to an existing resource, and custom resources not appropriate for inclusion in the FHIR specification?

• A. DocumentReference
• B. Binary
• C. Basic
• D. Parameters

Answer: (C)

When you have information that doesn’t fit any defined FHIR resource, you use a flexible catch‑all container. The Basic resource is designed for exactly this: it can represent concepts not yet defined in FHIR, narrative-only items that don’t map to an existing resource, and custom pieces of data that aren’t appropriate for inclusion in the official specification. You label the Basic with a code to describe what it is, optionally link it to a subject (like a patient), and credit an author. You can also extend it with extra data as needed. This makes Basic ideal for provisional concepts, nonstandard narratives, or experimental data that shouldn’t force-fit another resource.

Documents like DocumentReference are meant to point to external documents, and Binary stores raw binary data, while Parameters is used for inputs/outputs to operations. These don’t provide the flexible, generic container that Basic offers for undefined or custom content.