| Value | Category | Cases | |
|---|---|---|---|
| -9 | Don't know (spontaneous) | 2 |
1.3%
|
| -7 | Does not apply | 2 |
1.3%
|
| 0 | No obstacle | 26 |
17.4%
|
| 1 | Minor obstacle | 38 |
25.5%
|
| 2 | Moderate obstacle | 45 |
30.2%
|
| 3 | Major obstacle | 29 |
19.5%
|
| 4 | Very severe obstacle | 7 |
4.7%
|