Biopsychosocial Model

Based on the biopsychosocial (BPS) medical model, this study focuses on HPV vaccination behavior among adolescent females. It aims to explore the influence of multidimensional factors-including biological characteristics, psychological factors, and family and social environments-on vaccination behavior, and to evaluate the effectiveness of a comprehensive HPV vaccination intervention program designed for joint participation by adolescents and their parents. This study employs a prospective, multicenter, randomized, open-label, parallel-group design. Participants-girls and adolescents aged 9-17 who are scheduled to receive or have not yet completed HPV vaccination, along with their primary caregivers-were recruited from our hospital and collaborating pediatric/maternal and child health institutions both domestically and internationally. Participants were randomly assigned in a 1:1 ratio to an intervention group and a control group. In addition to routine vaccination clinic counseling, the intervention group received a comprehensive HPV vaccination intervention program based on the BPS model, including: structured health education materials (illustrated booklets/short videos); structured communication and shared decision-making support in the clinic setting; continuous information dissemination and vaccination reminders via platforms such as WeChat; and personalized follow-up and Q\&A sessions for families with high vaccine hesitancy; The control group received standard routine education and vaccination services. The primary outcome was the proportion of adolescents who completed the first dose of the HPV vaccine within 3 months of enrollment; secondary outcomes included the proportion completing the full vaccination series within 6 months, changes in vaccine hesitancy levels and HPV-related knowledge, changes in anxiety/depression levels among adolescents and caregivers, and changes in the quality of parent-child communication regarding health and vaccination as well as family decision-making patterns. This study is expected to identify key bio-psycho-social determinants of HPV vaccination behavior among adolescent females, validate the effectiveness of the comprehensive BPS intervention in increasing vaccination rates and improving decision-making experiences and psychosocial outcomes, and provide evidence-based guidance and scalable practical pathways for pediatric and related specialty clinics to implement adolescent vaccination health promotion and family shared decision-making services.