| Value | Category | Cases | |
|---|---|---|---|
| -9 | Don't know (spontaneous) | 115 |
6.9%
|
| -7 | Does not apply | 307 |
18.5%
|
| 0 | No obstacle | 301 |
18.1%
|
| 1 | Minor obstacle | 237 |
14.3%
|
| 2 | Moderate obstacle | 265 |
15.9%
|
| 3 | Major obstacle | 250 |
15%
|
| 4 | Very severe obstacle | 188 |
11.3%
|