| Vertigo grade | |
|---|---|
| 1 (Normal) | No vertigo |
| 2 (Mild) | Mild vertigo, no autonomic symptoms |
| 3 (Moderate) | Moderate vertigo, nausea occurred |
| 4 (Moderately severe) | Moderately severe vertigo, nausea and vomiting occurred |
| 5 (Severe) | Severe vertigo, nausea and vomiting occurred, immovable |