Hagerman B
Scand Audiol Suppl. 1984;21:1-25.
The aim of this study was to provide more knowledge about the influence of various factors on the reliability of speech audiometric measurements. On the basis of these data, new material on speech has also been developed for measurements of the speech reception threshold in noise. In a theoretical and a clinical investigation it has been shown that the reliability of speech discrimination scores may be predicted by using the binomial distribution. The reliability mainly depends on the score obtained and on the length of the word list. Curves with confidence intervals as well as diagrams which indicate when two different discrimination results deviate significantly from each other are presented. On the whole, the reliability is surprisingly poor. The reliability of speech reception threshold (SRT) measurements was studied by computer simulations and clinical studies. The SRT results of "subjects" who had poor speech discrimination were unreliable and were greatly affected by the level at which the test started. Some new methods were also simulated, one of which (the 2x4-word method) was 8% faster and also somewhat more reliable in the clinical studies than the ordinary 10-word method. It was also less affected by the patient's speech discrimination. Several speech lists with exactly the same content of sound, but with new sentences, were obtained by editing a list of ten spoken Swedish sentences in a computer. A noise was synthesized from the speech material by the computer to obtain the exact same spectrum of the speech and the noise. This material was tested monaurally on normal-hearing subjects and hearing-impaired subjects. A very steep intelligibility curve was obtained in noise (25%/dB), which gave a standard deviation of only 0.44 dB at repeated threshold measurements in noise for the normal-hearing subjects when the learning effect was outbalanced. This figure increased to 1.1 dB for those with severely impaired hearing. The learning effect between the first and the second thresholds did not exceed 1 dB. The threshold values ranged from -8 to -5 dB signal-to-noise ratio for those with normal hearing and from -7 to +7 dB for those with impaired hearing. The new sentence and noise material developed is well suited for clinical measurements of the speech reception threshold in noise.
本研究的目的是提供更多关于各种因素对言语测听测量可靠性影响的知识。基于这些数据，还开发了用于测量噪声中言语接受阈的新言语材料。在一项理论和临床研究中表明，言语辨别分数的可靠性可以通过使用二项分布来预测。可靠性主要取决于获得的分数和单词列表的长度。给出了带有置信区间的曲线以及表明两个不同辨别结果何时彼此显著偏离的图表。总体而言，可靠性出奇地低。通过计算机模拟和临床研究对言语接受阈（SRT）测量的可靠性进行了研究。言语辨别能力差的“受试者”的SRT结果不可靠，并且受到测试开始水平的极大影响。还模拟了一些新方法，其中一种方法（2x4单词法）在临床研究中比普通的10单词法快8%，并且在某种程度上更可靠。它也受患者言语辨别的影响较小。通过在计算机中编辑十个瑞典语口语句子的列表，获得了几个声音内容完全相同但句子不同的言语列表。计算机从言语材料中合成噪声，以获得与言语和噪声完全相同的频谱。该材料在听力正常的受试者和听力受损的受试者上进行了单耳测试。在噪声中获得了非常陡峭的可懂度曲线（25%/dB），当学习效应得到平衡时，对于听力正常的受试者，在噪声中重复阈值测量时标准偏差仅为0.44 dB。对于听力严重受损的受试者，这个数字增加到1.1 dB。第一次和第二次阈值之间的学习效应不超过1 dB。听力正常的受试者的阈值范围为信噪比-8至-5 dB，听力受损的受试者的阈值范围为-7至+7 dB。所开发的新句子和噪声材料非常适合于临床测量噪声中的言语接受阈。
