Interaction models on the association between HPV vaccination and cervical screening attendance (n=261 434)
| Model | Exposure status | Crude attendance n (%) | HR (95% CI) |
| Interaction model 1: vaccination and education* | |||
| Compulsory school (<9 years) | Unvac. | 12 799 (61.2) | ref. |
| Vac. | 612 (58.3) | 1.06 (0.98 to 1.15) | |
| High school (9–12 years) | Unvac. | 74 178 (74.1) | ref. |
| Vac. | 9219 (71.3) | 1.07 (1.04 to 1.09) | |
| University (>12 years) | Unvac. | 60 390 (74.3) | ref. |
| Vac. | 16 228 (77.3) | 1.13 (1.11 to 1.15) | |
| Missing | Unvac. | 10 116 (42.3) | ref. |
| Vac. | 147 (51.2) | 1.13 (0.96 to 1.33) | |
| Interaction model 2: vaccination and income† | |||
| Quartile 1 | Unvac. | 34 748 (58.3) | ref. |
| Vac. | 3178 (69.6) | 1.22 (1.18 to 1.27) | |
| Quartile 2 | Unvac. | 39 866 (71.2) | ref. |
| Vac. | 6012 (74.2) | 1.17 (1.14 to 1.20) | |
| Quartile 3 | Unvac. | 41 505 (76.8) | ref. |
| Vac. | 7662 (76.0) | 1.10 (1.08 to 1.13) | |
| Quartile 4 | Unvac. | 39 874 (77.6) | ref. |
| Vac. | 9514 (74.8) | 1.03 (1.00 to 1.05) | |
| Missing | Unvac. | 1294 (26.2) | ref. |
| Vac. | 2 (66.7) | 2.96 (0.74 to 11.86) | |
| Interaction model 3: vaccination and migration history‡ | |||
| Born in Sweden | Unvac. | 134 936 (75.5) | ref. |
| Vac. | 25 401 (74.9) | 1.09 (1.08 to 1.11) | |
| Immigrated ≥10 years ago | Unvac. | 7950 (55.8) | ref. |
| Vac. | 774 (65.9) | 1.52 (1.41 to 1.64) | |
| Immigrated <10 years ago | Unvac. | 14 401 (43.8) | ref. |
| Vac. | 193 (53.5) | 1.29 (1.12 to 1.48) | |
*HR adjusted for income, migration history and an interaction term between vaccination and education.
†HR adjusted for education, migration history and an interaction term between vaccination and income.
‡HR adjusted for income, education and an interaction term between vaccination and migration history.
HPV, human papillomavirus; Unvac, unvaccinated; Vac., HPV vaccinated with≥1 dose.