| Value | Category | Cases | |
|---|---|---|---|
| -9 | Don't know (spontaneous) | 2 |
0.3%
|
| -7 | Does not apply | 6 |
1%
|
| 0 | No obstacle | 453 |
78.1%
|
| 1 | Minor obstacle | 34 |
5.9%
|
| 2 | Moderate obstacle | 35 |
6%
|
| 3 | Major obstacle | 35 |
6%
|
| 4 | Very severe obstacle | 15 |
2.6%
|
| Sysmiss | 1 |