Erdo Index indicates your overall hearing condition.
Erdo's hearing test includes high frequency test and pure tone test. Erdo index is the score given to you based on the results of both tests.
An adult with a normal hearing should be able to hear frequencies higher than 10,000 Hz in the high-frequency hearing test. A child can even hear up to 20,000 Hz, which is the human hearing limit.
Young adults should be able to hear sound levels of 20 dB HL at frequent frequencies that people hear in their daily life such as 500, 1,000, 2,000, 4,000, and 8,000 Hz. If they cannot hear these frequencies unless the sound level exceeds 20 dB HL, they are generally regarded as suffering from different levels of hearing loss.
The Erdo index of young adults should range from A+ to B+, and the index decreases as they age.
According to the standards, Erdo index can be classified into the 5 rankings as below:
|A（A+、A、A-）||Your have a normal hearing, but you should still have regular check-ups. The results are further classified into A+, A, and A-.|
|B（B+、B、B-）||You have a mild hearing loss, so you should keep an eye on your hearing. The results are further classified into B+, B, and B-.|
|C||You have a moderate hearing loss. We suggest that you go to a doctor for further check-ups.|
|D||You have a moderately severe hearing loss. We suggest that you go to a doctor for further check-ups.|
|E||You have a severe hearing loss. We suggest that you go to a doctor for further check-ups.|
Generally speaking, young adults' Erdo index should be somewhere between A+ and B+, but the index varies because of how they attend to their ears and their family hearing history.
Nonetheless, our hearing gradually degrades as we age. The highest frequency we hear gradually decreases from 18,000 to 16,000, and even to 14,000 Hz. On the other hand, the sound level of the frequent frequencies we hear may rise gradually. For example, the sounds that we can hear at the level of 20 dB may not be heard unless they reach 40 or 50 dB once we grow older.
That is to say, the older we are, the lower our Erdo index gets. According to statistics, around one third of old people over 65 years of age can only hear the frequent frequencies when the sound level exceeds 40 dB, rendering an Erdo index of below B.
We advise that you take into account both the Erdo index and hearing age at the same time in order to really know your hearing condition.
※ This test is for informational purposes only and is not intended to replace a professional hearing evaluation. Please consult a doctor if necessary.