| Value | Category | Cases | |
|---|---|---|---|
| -9 | Don't know (spontaneous) | 6 |
1.7%
|
| -7 | Does not apply | 7 |
1.9%
|
| 0 | No obstacle | 186 |
51.7%
|
| 1 | Minor obstacle | 41 |
11.4%
|
| 2 | Moderate obstacle | 58 |
16.1%
|
| 3 | Major obstacle | 40 |
11.1%
|
| 4 | Very severe obstacle | 22 |
6.1%
|