| Value | Category | Cases | |
|---|---|---|---|
| -9 | Don't know (spontaneous) | 2 |
1.3%
|
| -7 | Does not apply | 2 |
1.3%
|
| 0 | No obstacle | 99 |
65.1%
|
| 1 | Minor obstacle | 12 |
7.9%
|
| 2 | Moderate obstacle | 16 |
10.5%
|
| 3 | Major obstacle | 17 |
11.2%
|
| 4 | Very severe obstacle | 4 |
2.6%
|