| Type | Hearing Recovery |
|---|---|
| 1. Complete recovery | Final hearing better than 25㏈ |
| 2. Partial recovery | More than 15㏈ gain, final hearing 25-45㏈ |
| 3. Slight improvement | More than 15㏈ gain, final poorer than 45㏈ |
| 4. No improvement | Less than 15㏈ gain, final hearing 75㏈ |