Hosseinabad Hedieh Hashemi, Bai Xiuqin
Department of Audiology and Speech Language Pathology, College of Health and Public Service, University, of North Texas, Denton, Texas, USA.
Department of Mathematics, Eastern Washington University, Spokane, Washington, USA.
Int J Lang Commun Disord. 2023 Sep-Oct;58(5):1814-1828. doi: 10.1111/1460-6984.12913. Epub 2023 Jun 9.
Intelligibility measurement is influenced by the characteristics of a speaker, listener and contextual factors. This study addresses the clinical problem of measuring speech intelligibility in children with velopharyngeal insufficiency (VPI) in real-world conditions.
The purpose of the study was to investigate the effects of background noise on speech intelligibility in speakers with velopharyngeal insufficiency (VPI) compared to typical speech. The study further determined the contribution of nasalance and articulation accuracy in judgments of intelligibility.
METHODS & PROCEDURES: Fifteen speakers diagnosed with VPI and their typical peers provided audio recordings of 20 sentences from the Hearing in Noise Test. Speech samples were presented over quiet and noise (+5 dB signal-to-noise ratio) conditions to 70 naïve listeners. Intelligibility scores from naïve listeners' orthographic transcriptions were obtained as the percentage of correctly identified words.
OUTCOMES & RESULTS: A repeated-measures analysis of variance showed diagnosis of VPI (F(1, 28) = 13.44, p = 0.001, and presence of noise (F(1, 28) = 39.18, p < 0.001) significantly affected the intelligibility scores. There was no interaction between the diagnosis of VPI and noise (F(1, 28) = 0.06, p = 0.80). The multivariate regression analysis indicated that nasalance and articulation accuracy explain a significant amount of variance in the intelligibility scores of VPI speakers in quiet (F(2, 12) = 7.11, p < 0.05, R = 0.55, R = 0.47) and noise (F(2, 12) = 6.32, p < 0.05, R = 0.51, R = 0.43), but the significance mainly came from the effect of percentage of consonants correct (β = 0.97, t(12) = 2.90, p = 0.01). Percentage of consonants correct significantly increased the speech intelligibility in either with or without noise conditions.
CONCLUSIONS & IMPLICATIONS: The current work suggests that background noise will significantly affect reductions in intelligibility in both groups; the effect is more prominent in VPI speech. It was also further noted that articulation accuracy significantly affected intelligibility in quiet and noise rather than nasalance scores.
What is already known on the subject Intelligibility measurement is influenced by the characteristics of a speaker, listener and contextual factors. Accordingly, it is essential to determine the degree to which speech assessments in the clinic can predict communication difficulties in the presence of background noise in real life. Background noise can adversely cause speech intelligibility degradation in individuals with speech disorders. What this study adds The study examined the effects of background noise on speech intelligibility in speakers with velopharyngeal insufficiency (VPI) secondary to cleft palate compared to typical speech. The study results suggested that the presence of background noise will significantly affect reductions in intelligibility in both groups; however, the effect is more prominent in VPI speech. What are the clinical implications of this work? We found out that the intelligibility of VPI speech is lower in the presence of background noise, and therefore, assessments of speech intelligibility in clinical settings should take this into account. To ensure effective communication in noisy environments, recommended strategies include selecting quiet locations, eliminating potential distractions and supplementing communication with nonverbal cues. It is important to recognize that the effectiveness of these strategies may vary depending on the individual and the specific communication context.
可懂度测量受说话者、听众的特征以及语境因素的影响。本研究旨在解决在现实环境中测量腭咽功能不全（VPI）儿童言语可懂度的临床问题。
本研究的目的是调查背景噪声对腭咽功能不全（VPI）患者与正常言语者言语可懂度的影响。该研究还进一步确定了鼻化度和发音准确性在可懂度判断中的作用。
15名被诊断为VPI的患者及其正常同龄人提供了来自《噪声环境下听力测试》中的20个句子的录音。语音样本在安静和噪声（信噪比为+5dB）条件下播放给70名未受过训练的听众。从未受过训练的听众的正字法转录中获得可懂度分数，以正确识别单词的百分比表示。
重复测量方差分析显示，VPI诊断（F(1, 28) = 13.44, p = 0.001）和噪声的存在（F(1, 28) = 39.18, p < 0.001）显著影响可懂度分数。VPI诊断与噪声之间没有交互作用（F(1, 28) = 0.06, p = 0.80）。多元回归分析表明，鼻化度和发音准确性在安静（F(2, 12) = 7.11, p < 0.05, R = 0.55, R = 0.47）和噪声（F(2, 12) = 6.32, p < 0.05, R = 0.51, R = 0.43）条件下能够解释VPI患者可懂度分数的大量变异，但显著性主要来自辅音正确率的影响（β = 0.97, t(12) = 2.90, p = 0.01）。辅音正确率在有无噪声条件下均显著提高了言语可懂度。
当前研究表明，背景噪声会显著影响两组患者的可懂度降低；这种影响在VPI言语中更为突出。还进一步指出，发音准确性在安静和噪声环境中对可懂度的影响显著，而非鼻化度分数。
关于该主题已知的信息 可懂度测量受说话者、听众的特征以及语境因素的影响。因此，确定临床言语评估在现实生活中存在背景噪声时能够预测沟通困难的程度至关重要。背景噪声会对言语障碍患者的言语可懂度产生不利影响。本研究补充的内容
该研究调查了背景噪声对腭裂继发腭咽功能不全（VPI）患者与正常言语者言语可懂度的影响。研究结果表明，背景噪声的存在会显著影响两组患者的可懂度降低；然而，这种影响在VPI言语中更为突出。这项研究的临床意义是什么？我们发现，在存在背景噪声的情况下，VPI言语的可懂度较低，因此，临床环境中言语可懂度的评估应考虑到这一点。为确保在嘈杂环境中的有效沟通，推荐的策略包括选择安静的地点、消除潜在干扰以及用非语言线索辅助沟通。重要的是要认识到，这些策略的有效性可能因个体和具体沟通情境而异。
