| Value | Category | Cases | |
|---|---|---|---|
| -9 | Don't know (spontaneous) | 23 |
5.9%
|
| -7 | Does not apply | 38 |
9.8%
|
| 0 | No obstacle | 134 |
34.5%
|
| 1 | Minor obstacle | 125 |
32.2%
|
| 2 | Moderate obstacle | 58 |
14.9%
|
| 3 | Major obstacle | 10 |
2.6%
|
| 4 | Very severe obstacle | 0 |
0%
|