Recommendation ITU-T H.821 is a transposition of Continua Health Alliance Test Tool DG2013, Test Suite Structure & Test Purposes, HRN Interface (Version 1.2, 2014-01-24), that was developed by the Continua Health Alliance. A number of versions of this specification existed before transposition.

This Recommendation includes an electronic attachment with the protocol implementation conformance statements (PICS) and the protocol implementation extra information for testing (PIXIT) required for the implementation of Annex A.