| Value | Category | Cases | |
|---|---|---|---|
| -9 | NIU (not in universe) | 104 |
4.5%
|
| 1 | yes, effective at preventing pregnancy | 2018 |
87.4%
|
| 2 | no, not effective at preventing pregnancy | 176 |
7.6%
|
| 98 | don't know | 11 |
0.5%
|
| 9999995 | missing:impute | 0 |
0%
|
| Sysmiss | 474 |