| Value | Category | Cases | |
|---|---|---|---|
| -9 | Don't know (spontaneous) | 3 |
0.5%
|
| -7 | Does not apply | 10 |
1.7%
|
| 0 | No obstacle | 201 |
34.7%
|
| 1 | Minor obstacle | 36 |
6.2%
|
| 2 | Moderate obstacle | 83 |
14.3%
|
| 3 | Major obstacle | 147 |
25.3%
|
| 4 | Very severe obstacle | 100 |
17.2%
|
| Sysmiss | 1 |