Background: Cervical cancer (CC) screening is crucial for reducing its incidence. However, encouraging participation among under-screened women remains challenging. Portugal's decentralized health regions provide an ideal case study due to a significant proportion of eligible women avoiding regular screening. Globally, self-sampling has emerged as a promising solution to enhance screening attendance. This study aims to assess self-sampling acceptance among under-screened women in central Portugal, contributing to the existing knowledge of self-sampling in CC screening. Methods: 801 women aged 30-59, not participating in the Central Region's CC Screening for 4 or more years, were randomly recruited. Women who accepted to participate in the study received cervicovaginal self-sampling kits at home. Women with a positive high-risk human papillomavirus (hr-HPV) test result were invited for gynaecological follow-up. Results: Among the 687 eligible women, 307 (44.7%) accepted, and 198 (28.8%) provided specimens for hr-HPV testing. Out of twelve positive cases, eleven underwent gynaecological follow-up, identifying six cervical lesions. Conclusions: The study highlights the potential of self-sampling and HPV testing to enhance CC screening in Portugal, with encouraging acceptance and effective detection of cervical lesions. These findings offer a promising solution for addressing under-screening among eligible women in the decentralized health regions of Portugal.

Pereira SG, Nobre L, and Ribeiro M are employed by Infogene, while Prazeres H and Nobre RJ hold partnership roles. Infogene acts as the distributor of the self-sampling device Qvintip in Portugal.

This study was partially supported by Infogene, covering the costs of nucleic acid extraction and HPV testing. The self-sampling kits were provided free of charge by Aprovix AB. The logistical costs associated with sending invitation letters, reminder letters, and self-sampling kits, as well as the telephone calls, were covered by the Central Regional Health Administration (ARS Centro). Gynaecology consultation, cytological diagnosis, and anatomopathological examination were covered by the Portuguese Institute of Oncology at Coimbra.

I confirm all relevant ethical guidelines have been followed, and any necessary IRB and/or ethics committee approvals have been obtained.

Yes

The details of the IRB/oversight body that provided approval or exemption for the research described are given below:

The self-sampling of cervicovaginal fluid was carried out with informed consent and the study received approval from the Ethics Committee of the Central Regional Health Administration of Portugal (Study n. 23/2018). The study was conducted from October 2018 to September 2019, following the principles of the Declaration of Helsinki.

I confirm that all necessary patient/participant consent has been obtained and the appropriate institutional forms have been archived, and that any patient/participant/sample identifiers included were not known to anyone (e.g., hospital staff, patients or participants themselves) outside the research group so cannot be used to identify individuals.

Yes

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All data produced in the present work are contained in the manuscript