Development and validation of the Mandarin matrix sentence test in noise

Abstract

Objective: Development of the Mandarin Chinese matrix (CMNmatrix) sentence test for speech intelligibility measurements in noise according to the international standard procedure. Design: A 50-word base matrix representing the distribution of phonemes and lexical tones of spoken Mandarin was established. The CMNmatrix consists of a corpus of phonologically balanced 50 words, with a construction of 10 names, 10 verbs, 10 numerals, 10 adjectives, and 10 nouns. 100 sentences capturing all the co-articulations of two consecutive words were recorded. Word-specific speech recognition functions, speech reception thresholds (SRT: signal-to-noise ratio, SNR, that provides 50% speech intelligibility), and slopes were obtained from measurements at fixed SNRs. The speech material was homogenized in intelligibility by applying level corrections up to ± 2 dB. Subsequently, the CMNmatrix test was evaluated: The comparability of test lists was measured at two fixed SNRs. To investigate the training effect and establish the reference data, speech recognition was measured adaptively Study sample: Overall, 80 normal-hearing native Mandarin-speaking listeners. Results: Multi-center evaluation measurements confirmed that test lists are equivalent in intelligibility, with a mean SRT of -10.1 ± 0.1 dB SNR and a slope of 13.1 ± 0.9 %/dB. The reference SRT is -9.3 ± 0.8 and -11.2 ± 1.2 dB SNR for the open- and closed-set response format, respectively. Conclusions: The CMNmatrix test is suitable for accurate and internationally comparable speech recognition measurements in noise.