HPV self-sampling among cervical cancer screening users in Spain: A randomized clinical trial of on-site training to increase the acceptability.

A randomized clinical trial was conducted to compare the impact of two different instructions on vaginal self-sampling in its acceptability and willingness for future screening rounds among women attending cervical cancer screening (CCS). From November 2018 to May 2021, women aged 30-65 living in Spain attending CCS were randomized 1:1 in two arms. In the "On-site training arm (TRA)", women took a self-sample at the primary health care centre following provider's instructions. In the "No on-site training arm (NO-TRA)" women only received instructions to take self-sample at home. All women had to return a new sample collected at home one month after the baseline visit and an acceptability questionnaire. The proportion of self-samples returned, and acceptability was computed by the study arm. A total of 1158 women underwent randomization, 579 women per arm. At follow-up, women in TRA were more likely to return the home sample than women in the NO-TRA (82.4% and 75.5% respectively; p = 0.005). Over 87% of all participants favoured home-based self-sampling approach for future CCS, similar by arm. Over 80% of women in both arms chose to collect and return the self-sample at a health centre or pharmacy. Home-based self-sampling was a highly accepted strategy for CCS in Spain. Trying it first with prior on-site training at the health centre significantly increased the sample's return suggesting that a provider's supervision raised confidence and adherence. It is an option to consider when moving to self-sampling in established CCS. Preferred delivery sites most likely contextual. Registration on ClinicalTrials.gov: NCT05314907.