| Variables | Measurement of the variable | Variable designs |
| Lack of control | 1 when the information is significant and 0 in the contrary | causemm |
| Driver carelessness | 1 when the information is significant and 0 in the contrary | causeimp |
| Bad parking | 1 when the information is significant and 0 in the contrary | casemst |
| Brake failure | 1 when the information is significant and 0 in the contrary | causup |
| Dangerous maneuvering | 1 when the information is significant and 0 in the contrary | causemda |
| Mechanical failure | 1 when the information is significant and 0 in the contrary | causem |
| Driver inattention | 1 when the information is significant and 0 in the contrary | causeina |
| Wheel bursting | 1 when the information is significant and 0 in the contrary | causecl |
| Excessive speed | 1 when the information is significant and 0 in the contrary | causevit |
| Bad overtaking | 1 when the information is significant and 0 in the contrary | causemde |