Classification of hearing loss (hypacusis) according to severity (WHO) including clinical recommendations.
| Degree of hearing loss | Moderate hearing loss(in pure tone audiogram* ) | Clinical findings | Clinical recommendation |
| Grade 0 (normal hearing) | 25 dB or better | Patient can hear whispered speech(no or only mild problems with communication) | Follow-up; check surgical indication for conductive hearing loss. |
| Grade I (low-grade hearing loss) | 26-40 dB | Colloquial speech is understood 1 m in front of the ear | Hearing aid may be recommended; in the case of conductive or mixed hearing loss, surgical treatment may be necessary. |
| Grade II (moderate hearing loss) | 41-60 dB | Loud speech is understood 1 m in front of the ear | Hearing aid recommended; in case of conductive hearing loss or combined hearing loss, surgical treatment may be necessary |
| Grade III (profound hearing loss) | 61-80 dB | Some words are understood in the better ear when speaking very loudly | Hearing aid required! If no hearing aid is possible, check whether other hearing aids (e.g. implantable hearing aid or cochlear implant) are possible; supportive lip reading and sign language if necessary |
| Grade IV (residual hearing or deafness) | ≥ 81 dB | No speech comprehension at maximum volume level | Hearing aid trial; failure usually indicates cochlear implantation; supportive lip-reading and sign language as appropriate |
* For mean hearing loss, mean hearing loss values are obtained for each ear separately. The following frequencies are examined: 500 Hz, 1,000 Hz, 2,000 Hz, and 4,000 Hz.