| Value | Category | Cases | |
|---|---|---|---|
| -9 | Don't know (spontaneous) | 3 |
0.5%
|
| -7 | Does not apply | 9 |
1.6%
|
| 0 | No obstacle | 418 |
72.1%
|
| 1 | Minor obstacle | 46 |
7.9%
|
| 2 | Moderate obstacle | 39 |
6.7%
|
| 3 | Major obstacle | 40 |
6.9%
|
| 4 | Very severe obstacle | 25 |
4.3%
|
| Sysmiss | 1 |