| Value | Category | Cases | |
|---|---|---|---|
| -9 | Don't know (spontaneous) | 0 |
0%
|
| -7 | Does not apply | 4 |
1.9%
|
| 0 | No obstacle | 35 |
16.7%
|
| 1 | Minor obstacle | 73 |
34.9%
|
| 2 | Moderate obstacle | 27 |
12.9%
|
| 3 | Major obstacle | 36 |
17.2%
|
| 4 | Very severe obstacle | 34 |
16.3%
|