Table 2.
Participation rate, stratified by age groups and screening history
| Directly mailed group | Opt-in group | Control group | ||||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Self-sampling | Cytology | Totala | Self-sampling | Cytology | Totala | Cytology | ||||||||
| N | n (%) | n (%) | n (%) | PD1 (95% CI) |
RR1 (95% CI) | N | n (%) | n (%) | n (%) | PD2 (95% CI) |
RR2 (95% CI) | N | n (%) | |
| Age (years) | ||||||||||||||
| 30–39 | 1236 | 231 (18.7) | 264 (21.4) | 495 (40.0) | 13.4 (9.8–17.1) | 1.50 (1.34–1.69) | 1215 | 81 (6.7) | 316 (26.0) | 397 (32.7) | 6.1 (2.5–9.7) | 1.23 (1.09–1.39) | 1251 | 333 (26.6) |
| 40–49 | 1300 | 271 (20.9) | 260 (20.0) | 531 (40.8) | 13.3 (9.8–16.9) | 1.49 (1.33–1.66) | 1353 | 126 (9.3) | 326 (24.1) | 452 (33.4) | 5.9 (2.4–9.4) | 1.21 (1.08–1.36) | 1342 | 369 (27.5) |
| 50–64 | 729 | 133 (18.2) | 83 (11.4) | 216 (29.6) | 11.5 (7.1–15.9) | 1.63 (1.35–1.99) | 696 | 63 (9.1) | 97 (13.9) | 160 (22.9) | 4.9 (0.6–9.2) | 1.27 (1.03–1.57) | 669 | 121 (18.1) |
| Total | 3265 | 635 (19.4) | 607 (18.6) | 1242 (38.0) | 12.8 (10.6–15.0) | 1.51 (1.40–1.62) | 3264 | 270 (8.3) | 739 (22.6) | 1009 (30.9) | 5.7 (3.5–7.9) | 1.23 (1.13–1.32) | 3262 | 823 (25.2) |
| Screened in previous screening roundb | ||||||||||||||
| Not screened | 1298 | 203 (15.6) | 97 (7.5) | 300 (23.1) | 14.9 (12.2–17.7) | 2.83 (2.29–3.49) | 1272 | 76 (5.9) | 95 (7.5) | 171 (13.4) | 5.2 (2.9–7.7) | 1.65 (1.30–2.08) | 1249 | 102 (8.2) |
| Screened | 1967 | 432 (21.9) | 510 (25.9) | 942 (47.9) | 12.1 (9.0–15.1) | 1.34 (1.24–1.44) | 1992 | 194 (9.7) | 644 (32.3) | 838 (42.1) | 6.3 (3.2–9.3) | 1.17 (1.09–1.27) | 2013 | 721 (35.8) |
| Screening historyb | ||||||||||||||
| Unscreened | 604 | 81 (13.4) | 39 (6.5) | 120 (19.9) | 12.6 (8.8–16.4) | 2.75 (1.96–3.84) | 595 | 16 (2.7) | 36 (6.1) | 52 (8.7) | 1.5 (−1.6–4.6) | 1.21 (0.82–1.79) | 567 | 41 (7.2) |
| Underscreened | 802 | 135 (16.8) | 78 (9.7) | 213 (26.6) | 12.3 (8.4–16.2) | 1.86 (1.52–2.28) | 842 | 71 (8.4) | 97 (11.5) | 168 (19.9) | 5.7 (2.1–9.3) | 1.4 (1.13–1.73) | 842 | 120 (14.3) |
| Regularly screened | 1859 | 419 (22.5) | 490 (26.4) | 909 (48.9) | 13.2 (10.0–16.3) | 1.37 (1.27–1.48) | 1827 | 183 (10.0) | 606 (33.2) | 789 (43.2) | 7.5 (4.3–10.6) | 1.21 (1.12–1.31) | 1853 | 662 (35.7) |
Participation rate is calculated as having a self-sample or a cervical cytology sample within 180 days after the second reminder. N: Number of randomized women. n: Number of participants in the group
%: Row percentages. aTotal number of returned self-samples and cervical cytology samples. bSee classification of screening history for definitions
Abbreviations:
PD1: Participation difference in the total participation in the directly mailed group compared to the total participation in the control group
RR1: Total participation in the directly mailed group compared to the total participation in the control group
PD2: Participation difference in the total participation in the opt-in group compared to the total participation in the control group
RR2: Total participation in the opt-in group compared to the total participation in the control group