| Value | Category | Cases | |
|---|---|---|---|
| -9 | Don't know (spontaneous) | 11 |
3.6%
|
| -7 | Does not apply | 13 |
4.2%
|
| 0 | No obstacle | 191 |
62.2%
|
| 1 | Minor obstacle | 46 |
15%
|
| 2 | Moderate obstacle | 25 |
8.1%
|
| 3 | Major obstacle | 18 |
5.9%
|
| 4 | Very severe obstacle | 3 |
1%
|