| Value | Category | Cases | |
|---|---|---|---|
| -9 | Don't know (spontaneous) | 0 |
0%
|
| 1 | One hour or less | 1 |
0.7%
|
| 2 | 1 |
0.7%
|
|
| 6 | 2 |
1.3%
|
|
| 10 | 1 |
0.7%
|
|
| 12 | 1 |
0.7%
|
|
| 18 | 1 |
0.7%
|
|
| NA | 144 |
95.4%
|