Table 1.
Classification of permanent childhood deafness
| Classification | Category |
|---|---|
| Mechanism | Conductive |
| Sensorineural | |
| Mixed (conductive and sensorineural components) | |
| Auditory neuropathy | |
| Degree | Slight (16–25 dB HL) |
| Mild (26–40 dB HL) | |
| Moderate (41–55 dB HL) | |
| Moderately severe (56–70 dB HL) | |
| Severe (71–90 dB HL) | |
| Profound (>90 dB HL) | |
| Symmetry | Bilateral–symmetric |
| Bilateral–asymmetric | |
| Unilateral | |
| Progression | Stable |
| Progressive | |
| Fluctuating | |
| Onset | Congenital |
| Prelingual | |
| Infantile | |
| Postlingual | |
| Childhood | |
| Adult | |
| Frequency pattern of deafness | High frequency (downsloping) |
| Low frequency (upsloping) | |
| Mid-frequency (cookie bite) | |
| All frequencies (flat) | |
| Associated clinical findings | Nonsyndromic (no other clinical findings) |
| Syndromic (other clinical findings) | |
| Nonsyndromic mimics (syndromic HL diagnosed when other clinical findings are not yet apparent) |
HL hearing level.