| Value | Category | Cases | |
|---|---|---|---|
| -9 | Don't know (spontaneous) | 39 |
5.1%
|
| -7 | Does not apply | 34 |
4.4%
|
| 0 | No obstacle | 265 |
34.3%
|
| 1 | Minor obstacle | 146 |
18.9%
|
| 2 | Moderate obstacle | 143 |
18.5%
|
| 3 | Major obstacle | 101 |
13.1%
|
| 4 | Very severe obstacle | 44 |
5.7%
|