Publication
Altered quality of the phonetic-acoustic information in the speech signal in the case of motor speech disorders may reduce its intelligibility. Monitoring intelligibility is part of the standard clinical assessment of patients. It is also a valuable tool to index the evolution of the speech disorder. However, measuring intelligibility raises methodological debates concerning: the type of linguistic material on which the assessment is based (non-words, words, continuous speech), the evaluation protocol and type of scores (scale-based rating, transcription or recognition tests), and the advantages and disadvantages of listener vs. automatic-based approaches (subjective vs. objective, expertise level, types of models used). In this paper, the intelligibility of the speech of 32 French patients presenting mild to moderate dysarthria and 17 elderly speakers is assessed with five different methods: impressionistic clinician judgment on continuous speech, number of words recognized in an interactive face-to-face setting and in an on-line testing of the same material by 75 judges, automatic feature-based and automatic speech recognition-based methods (both on short sentences). The implications of the different methods for clinical practice are discussed.