Abstract: ObjectiveTo assess the costs and benefits of two algorithms for cervical cancer screening in Belgium (1) high-risk human papillomavirus (HR-HPV) primary screening and (2) HR-HPV and liquid-based cytology (LBC) co-testing.MethodsA decision tree was adapted from published work and parameterised using HORIZON study data and Belgian cost and population data. The theoretical model represents two different screening algorithms for a cohort of 577 846 women aged 25-64 attending routine cervical screening. Scenario analyses were used to explore the impact of including vaccinated women and alternative pricing approaches. Uncertainty analyses were conducted.ResultsThe cost per woman screened was <euro>113.50 for HR-HPV primary screening and <euro>101.70 for co-testing, representing a total cost of <euro>65 588 573 and <euro>58 775 083, respectively, for the cohort; a 10% difference. For one screening cycle, compared to HR-HPV primary, co-testing resulted in 13 173 more colposcopies, 67 731 more HR-HPV tests and 477 020 more LBC tests. Co-testing identified 2351 more CIN2+ cases per year (27% more than HR-HPV primary) and 1602 more CIN3+ cases (24% more than HR-HPV primary) than HR-HPV primary.ConclusionIn Belgium, a co-testing algorithm could increase cervical pre-cancer detection rates compared to HR-HPV primary. Co-testing would cost less than HR-HPV primary if the cost of the HPV test and LBC were cost-neutral compared to the current cost of LBC screening but would cost more if the cost per HPV test and LBC were the same in both co-testing and HR-HPV primary strategies.