[Establishment of Mono-scaled Benefit/Risk Analysis of HPV Vaccine]

Decisions concerning approval of human papillomavirus (HPV) vaccines and their use are based on expert evaluation of the vaccines. However, the quantitative differences between vaccine benefits and risks are difficult for non-experts to understand. In this study, we developed a new method to calculate the benefits and risks of the HPV vaccines using disability-adjusted life year (DALY) as the mono-scaled weight for various benefits and risks relevant to the vaccines. We evaluated benefits as a gain of DALY values for cervical cancer and risks as the loss of DALY values for various adverse events by the vaccination. To calculate the loss of DALY values, we integrated all adverse events in the International Classification of Diseases chapters. The novel method reflected the men-women ratio of this epidemiological disease to a certain extent. Among the vaccinated women, 111372 and 477190 received a bivalent and quadrivalent vaccine, respectively. The DALY rate of cervical cancer was 148.7. The calculated benefit for the bivalent and quadrivalent vaccines was 149.1 and 638.8, respectively, and set as the theoretical maximum. The risk was calculated as 129.3 and 49.6 in the bivalent and quadrivalent vaccines, respectively. Since HPV vaccines prevent several other cancers, the benefit of the vaccination extends beyond the risk according to this new method.