| Value | Category | Cases | |
|---|---|---|---|
| -9 | Don't know (spontaneous) | 5 |
1.4%
|
| -7 | Does not apply | 16 |
4.4%
|
| 0 | No obstacle | 183 |
50.6%
|
| 1 | Minor obstacle | 62 |
17.1%
|
| 2 | Moderate obstacle | 58 |
16%
|
| 3 | Major obstacle | 27 |
7.5%
|
| 4 | Very severe obstacle | 11 |
3%
|