| Value | Category | Cases | |
|---|---|---|---|
| -9 | Don't know (spontaneous) | 4 |
1.8%
|
| -7 | Does not apply | 0 |
0%
|
| 0 | No obstacle | 38 |
17.4%
|
| 1 | Minor obstacle | 53 |
24.2%
|
| 2 | Moderate obstacle | 57 |
26%
|
| 3 | Major obstacle | 44 |
20.1%
|
| 4 | Very severe obstacle | 23 |
10.5%
|