| Type | Hearing recovery |
|---|---|
| I. Complete recovery | Final hearing better than 25㏈ |
| II. Partial recovery | More than 15㏈ gain, final hearing 24-25㏈ |
| III. Slight improvement | More than 15㏈ gain, final hearing poorer than 45㏈ |
| IV. No improvement | Less than 15㏈ gain, final hearing poorer than 75㏈ |