Objective assessment of speech that reflects meaningful changes in communication is crucial for clinical decision making and reproducible research. While existing objective assessments, particularly reference-based approaches, can capture intelligibility changes, they are often hindered by lack of explainability and the need for labor-intensive manual transcriptions. To address these issues, this work proposes the reference-free, explainable ASR Inconsistency Score. We evaluate this method on pathological speech in Dutch, Spanish and English, and compare its performance to a reference-based Word Error Rate (WER) baseline. Our results demonstrate that the ASR Inconsistency Score achieves a high correlation with expert perceptual ratings, with performance closely matching, and in one case exceeding, a standard reference-based Word Error Rate (WER) baseline.
@article{arxiv.2602.12723,
title = {Towards explainable reference-free speech intelligibility evaluation of people with pathological speech},
author = {Bence Mark Halpern and Thomas Tienkamp and Defne Abur and Tomoki Toda},
journal= {arXiv preprint arXiv:2602.12723},
year = {2026}
}