Erlandsson B, Håkanson H, Ivarsson A, Nilsson P, Sheppard H
Scand Audiol. 1983;12(4):265-71. doi: 10.3109/01050398309044430.
The hearing thresholds of a total of 58 workers aged 20 to 65 years were measured annually over a period of 4 years using Békésy sweep-frequency audiometry. Using these data, accurate values of the yearly rate of change of hearing threshold level were calculated. The rate of change of hearing threshold level due to presbyacusis was obtained from several data sets, and the rate of change of hearing threshold level due to noise was calculated. When the average hearing threshold level over the frequency range 2-8 kHz was considered, it was found to be possible to establish a significant rate of threshold shift caused by exposure to noise for yearly changes as small as approximately 2 dB. In the cases investigated about 30% of the ears showed a significant deterioration in hearing ability due to noise. When comparing the permanent threshold shift caused by noise in groups of younger and older workers, it was found that the younger workers exhibited less threshold shift than expected, whereas the older workers showed a greater threshold shift than expected.
在4年时间里，每年使用贝凯西扫频听力测定法对总共58名年龄在20至65岁之间的工人的听力阈值进行测量。利用这些数据，计算出听力阈值水平年变化率的准确值。从多个数据集中得出了因老年性耳聋导致的听力阈值水平变化率，并计算出了因噪声导致的听力阈值水平变化率。当考虑2至8千赫频率范围内的平均听力阈值水平时，发现对于小至约2分贝的年变化，有可能确定由噪声暴露引起的显著阈值偏移率。在所调查的案例中，约30%的耳朵因噪声导致听力能力显著下降。在比较年轻和年长工人组中由噪声引起的永久性阈值偏移时，发现年轻工人的阈值偏移比预期的要小，而年长工人的阈值偏移比预期的要大。
