Editing Mean Opinion Score (section)

=== Evolution and Extensions ===

Following the success of P.800, the ITU-T developed additional recommendations to clarify and extend MOS methodology:

* '''ITU-T P.800.1''' (2003, updated 2016): Established terminology for different types of MOS scores, distinguishing between listening quality subjective (MOS-LQS), listening quality objective (MOS-LQO), and listening quality estimated (MOS-LQE) to avoid confusion about the source and nature of scores.<ref>https://studylib.net/doc/8277727/itu-t-rec.-p.800.1--03-2003--mean-opinion-score--mos--ter</ref>
* '''ITU-T P.800.2''': Prescribed how MOS values should be reported, emphasizing that MOS scores from separate experiments cannot be directly compared unless explicitly designed for comparison and statistically validated.
* '''ITU-T P.808''' (2021): Addressed crowdsourcing methods for conducting subjective evaluations, recognizing the need for scalable approaches to MOS testing in the digital age.<ref>https://www.itu.int/rec/dologin_pub.asp?lang=e&id=T-REC-P.808-202106-I!!PDF-E&type=items</ref>