| Value | Category | Cases | |
|---|---|---|---|
| -9 | Don't know (spontaneous) | 7 |
1.6%
|
| -7 | Does not apply | 20 |
4.7%
|
| 0 | No obstacle | 137 |
31.9%
|
| 1 | Minor obstacle | 74 |
17.2%
|
| 2 | Moderate obstacle | 146 |
34%
|
| 3 | Major obstacle | 36 |
8.4%
|
| 4 | Very severe obstacle | 9 |
2.1%
|