Table 1 Summary of scenarios examined
Scenario name | Model | Vaccination? | Description |
|---|---|---|---|
Gradual change (simple method) | Simple | No | Assumes a gradual change to the new program in 2017 (no recall invitations sent to women aged >25 until after their first HPV screening test; current system where reminders are only sent to women who are 3Â months overdue for their next recommended test remains in place). Re-attendance is assumed to be equivalent to that observed under the current reminder-based system. |
Active recall 2018 (simple method) | Simple | No | Assumes an active recall invitation is sent in 2018 to all women due for screening who did not attend in 2017 ie sent two years or more after their most recent cytology screening test. Re-attendance following this invitation is assumed to be at least as high as that under a call-recall invitation system after a routine HPV test. |
Gradual change (detailed method) | Detailed | No | Assumes a gradual change to the new program in 2017 (no recall invitations sent to women aged >25 until after their first HPV screening test; current system where reminders are only sent to women who are 3Â months overdue for their next recommended test remains in place). Re-attendance is assumed to be equivalent to that observed under the current reminder-based system. |
Simple method – approximate vaccine effect | Simple | Yes | Simpler estimates assuming a gradual change to the new program in 2017 and approximating the effect of HPV vaccination: vaccine effect is applied to women born in 1981 or later (ie aged 26 or less for at least the first six months of the catch-up HPV vaccination program) |
Simple method – no vaccine effect | Simple | No | Simpler estimates assuming a gradual change to the new program in 2017 but no effect of HPV vaccination (what would have been observed under the new program in the absence of HPV vaccination) |
Detailed method with vaccination/Program change in 2017 with vaccination | Detailed | Yes | Detailed estimates assuming a gradual change to the new program in 2017 and taking into account the effect of HPV vaccination over time (best and most detailed estimates for likely future resource use) |
Detailed method – no vaccine effect/Program change in 2017 – no vaccine effect | Detailed | No | Detailed estimates assuming a gradual change to the new program in 2017 but no effect of HPV vaccination (what would have been observed under the new program in the absence of HPV vaccination): this counterfactual allows examination of the effect of the screening program change and demographic change only. |
Current practice with vaccination | Detailed | Yes | Detailed estimates of resource use in the absence of any change to the current program (see Additional file 1: Figure S2) but which take into account the effect of HPV vaccination: this counterfactual allows examination of the effect of HPV vaccination and demographic change only. |
Current practice – no vaccine effect | Detailed | No | Detailed estimates of resource use in the absence of any change to the current program and in the absence of HPV vaccination: this counterfactual allows examination of the effect of demographic change only. |