| Value | Category | Cases | |
|---|---|---|---|
| 0 | took the test every 2 or 3 years | 6 |
0.3%
|
| 1 | only once | 1574 |
79.3%
|
| 2 | every year | 113 |
5.7%
|
| 3 | every 6 months | 96 |
4.8%
|
| 4 | every 3 months | 74 |
3.7%
|
| 5 | took the test more than 3 times | 19 |
1%
|
| 6 | other | 6 |
0.3%
|
| 7 | took the test 2 times | 72 |
3.6%
|
| 8 | took the test 3 times | 26 |
1.3%
|
| 11 | .Z | 6253 |