Standards:

> ITU-T
ITU-T Recommendation P.800.1, Mean Opinion Score (MOS) Terminology, March 2003

This Recommendation provides a terminology which shall be used in conjunction with speech quality expressions in terms of Mean Opinion Score (MOS). The new terminology is motivated by the intention to avoid misunderstanding as to whether specific values of MOS are related to listening quality or conversational quality, and whether they originate from subjective tests, from objective models or from network planning models.

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