Frank T
Department of Communication Disorders, Penn State University, University Park 16802, USA.
Ear Hear. 2001 Apr;22(2):161-8. doi: 10.1097/00003446-200104000-00009.
The first purpose of this study was to determine high-frequency (8 to 16 kHz) thresholds for standardizing reference equivalent threshold sound pressure levels (RETSPLs) for a Sennheiser HDA 200 earphone. The second and perhaps more important purpose of this study was to determine whether repeated high-frequency thresholds using a Sennheiser HDA 200 earphone had a lower intrasubject threshold variability than the ASHA 1994 significant threshold shift criteria for ototoxicity.
High-frequency thresholds (8 to 16 kHz) were obtained for 100 (50 male, 50 female) normally hearing (0.25 to 8 kHz) young adults (mean age of 21.2 yr) in four separate test sessions using a Sennheiser HDA 200 earphone.
The mean and median high-frequency thresholds were similar for each test session and increased as frequency increased. At each frequency, the high-frequency thresholds were not significantly (p > 0.05) different for gender, test ear, or test session. The median thresholds at each frequency were similar to the 1998 interim ISO RETSPLs; however, large standard deviations and wide threshold distributions indicated very high intersubject threshold variability, especially at 14 and 16 kHz. Threshold repeatability was determined by finding the threshold differences between each possible test session comparison (N = 6). About 98% of all of the threshold differences were within a clinically acceptable range of +/-10 dB from 8 to 14 kHz. The threshold differences between each subject's second, third, and fourth minus their first test session were also found to determine whether intrasubject threshold variability was less than the ASHA 1994 criteria for determining a significant threshold shift due to ototoxicity. The results indicated a false-positive rate of 0% for a threshold shift > or = 20 dB at any frequency and a false-positive rate of 2% for a threshold shift >10 dB at two consecutive frequencies.
This study verified that the output of high-frequency audiometers at 0 dB HL using Sennheiser HDA 200 earphones should equal the 1998 interim ISO RETSPLs from 8 to 16 kHz. Further, because the differences between repeated thresholds were well within +/-10 dB and had an extremely low false-positive rate in reference to the ASHA 1994 criteria for a significant threshold shift due to ototoxicity, a Sennheiser HDA 200 earphone can be used for serial monitoring to determine whether significant high-frequency threshold shifts have occurred for patients receiving potentially ototoxic drug therapy.
本研究的首要目的是确定森海塞尔HDA 200耳机的高频（8至16千赫）阈值，以标准化参考等效阈值声压级（RETSPLs）。本研究的第二个或许更重要的目的是确定使用森海塞尔HDA 200耳机重复测量高频阈值时，受试者内部阈值变异性是否低于美国言语语言听力协会（ASHA）1994年规定的耳毒性显著阈值变化标准。
使用森海塞尔HDA 200耳机，在四个独立的测试环节中，对100名（50名男性，50名女性）听力正常（0.25至8千赫）的年轻成年人（平均年龄21.2岁）进行高频（8至16千赫）阈值测量。
每个测试环节的高频阈值均值和中位数相似，且随频率增加而升高。在每个频率上，高频阈值在性别、测试耳或测试环节方面无显著差异（p>0.05）。每个频率的中位数阈值与1998年ISO临时RETSPLs相似；然而，较大的标准差和较宽的阈值分布表明受试者间阈值变异性非常高，尤其是在14和16千赫时。通过找出每个可能的测试环节比较之间的阈值差异（N = 6）来确定阈值重复性。在8至14千赫范围内，约98%的阈值差异在临床上可接受的±10分贝范围内。还通过比较每个受试者第二次、第三次和第四次测试环节减去第一次测试环节的阈值差异，来确定受试者内部阈值变异性是否小于ASHA 1994年规定的因耳毒性导致显著阈值变化的标准。结果表明，在任何频率下阈值变化≥20分贝时假阳性率为0%，在两个连续频率下阈值变化>10分贝时假阳性率为2%。
本研究证实，使用森海塞尔HDA 200耳机时，0分贝听力级下高频听力计的输出应与1998年ISO临时RETSPLs在8至16千赫范围内相等。此外，由于重复阈值之间的差异远在±10分贝以内，且相对于ASHA 1994年规定的因耳毒性导致显著阈值变化的标准，假阳性率极低，因此森海塞尔HDA 200耳机可用于连续监测，以确定接受潜在耳毒性药物治疗的患者是否发生了显著的高频阈值变化。
