| Value | Category | Cases | |
|---|---|---|---|
| -9 | Don't know (spontaneous) | 0 |
0%
|
| -7 | Does not apply | 5 |
4.9%
|
| 0 | No obstacle | 36 |
35%
|
| 1 | Minor obstacle | 10 |
9.7%
|
| 2 | Moderate obstacle | 6 |
5.8%
|
| 3 | Major obstacle | 23 |
22.3%
|
| 4 | Very severe obstacle | 23 |
22.3%
|