| Value | Category | Cases | |
|---|---|---|---|
| -9 | Don't know (spontaneous) | 1 |
0.2%
|
| -7 | Does not apply | 13 |
2.2%
|
| 0 | No obstacle | 383 |
66%
|
| 1 | Minor obstacle | 35 |
6%
|
| 2 | Moderate obstacle | 49 |
8.4%
|
| 3 | Major obstacle | 56 |
9.7%
|
| 4 | Very severe obstacle | 43 |
7.4%
|
| Sysmiss | 1 |