| Severity scale | Severity scale code | Pain intensity | Skin integrity | Pressure of nail curvature on nail-fold | Redness | Discomfort incidence |
| Ingrown | 4 | Severe | Breached | Tightly pressed | Severe | Continuous |
| Very ingrowing | 3 | Moderate | At risk of breaching | Clearly presses | Moderate | Most of the time |
| Somewhat ingrowing | 2 | Mild | Skin intact | Pressing but can be pulled away | Mild | Some of the time |
| Slightly ingrowing | 1 | Some | Skin intact | Some risk | Some | Occasionally |
| Not ingrowing | 0 | None | Skin intact | No risk | None | None |