| Value | Category | Cases | |
|---|---|---|---|
| -9 | Don't know (spontaneous) | 52 |
4.7%
|
| -7 | Does not apply | 36 |
3.3%
|
| 0 | No obstacle | 85 |
7.8%
|
| 1 | Minor obstacle | 206 |
18.8%
|
| 2 | Moderate obstacle | 272 |
24.8%
|
| 3 | Major obstacle | 309 |
28.2%
|
| 4 | Very severe obstacle | 136 |
12.4%
|