HPV self-sampling and follow-up over two rounds of cervical screening in Australia - the iPap trial.

Objectives: Previously, based on 6 months of follow-up, we showed that HPV self-sampling improved participation in cervical screening compared to a reminder letter for Pap testing for never- and under-screened women. Here, we report follow-up and related screening outcomes for women who participated in the initial self-sampling over two screening rounds.

Setting: The randomised controlled trial was conducted in Australia.

Methods: Never- and under-screened women were randomly allocated to the HPV self-sampling or the reminder for Pap test arm and followed at 6 and 36 months since the kits were first mailed.

Results: The first round of HPV self-sampling kits were mailed from May-July 2014 to 12 572 women. After 36 months, 19% of never-screened and 9% of under-screened women returned a kit for HPV testing; 2.7% were HPV 16/18 and 5.8% non-16/18 HPV positive. Compliance with first round follow-up was 84% (95% CI: 77.1-89.5%). Non-compliant and cytology triage negative women were mailed another kit at 12 months. Compliance at 12-month follow-up was 59.3% (49.4 to 68.6%). Of 37 women with a 12-month repeat HPV, 70% were positive. Of women who tested negative for HPV in the first round (n = 1573), 25% attended regular screening in the next round and none had CIN2 + detected. The overall prevalence of CIN2 + was 8.5 per 1000 screened (4.8 to 13.9 per 1000).

Conclusion: While self-sampling can successfully engage women, compliance with repeat testing may require monitoring. The clinician-supported self-collection pathway now in use in Australia will likely improve women's engagement with follow-up.