Table 2. Descriptive statistics (n and %) for the indicators of screening history.
| Cases, n (%) | Controls, n (%) | |
|---|---|---|
|
Number of invitations before index
invitation | ||
| 0 | 611 (32) | 6135 (32) |
| 1 | 431 (23) | 4259 (22) |
| 2 | 327 (17) | 3206 (17) |
| 3 | 276 (14) | 2733 (14) |
| 4 | 155 (8) | 1562 (8) |
| 5–9 | 105 (6) | 1055 (6) |
| 10–12 | 2 (0) | 28 (0) |
|
Year of first invitation | ||
| 1992 | 683 (36) | 6720 (35) |
| 1993 | 621 (33) | 6237 (33) |
| 1994–1996 | 259 (14) | 2530 (13) |
| 1997–1999 | 167 (9) | 1770 (9) |
| 2000–2009 | 17 (9) | 1721 (9) |
|
Residential municipality at index
invitation | ||
| The same as in the first invitation | 1812 (95) | 18 073 (95) |
| Changed from the first invitation | 95 (5) | 905 (5) |
Note: The differences in frequencies between the cases and controls: for the number of invitations before index invitations P=0.999, for the year of invitation P=1.000 and for the change in residential municipality P=0.678.