| Safe interval for repeat of EC | ||
| After a month | 71 | 21.5 |
| After a week | 5 | 1.5 |
| After one year | 99 | 29.9 |
| Others | 15 | 4.5 |
| No response | 141 | 42.6 |
| Knowledge level | ||
| High (≥70%) | 141 | 42.6 |
| Low (<70%) | 190 | 57.4 |