Determinants of Pneumococcal Vaccination Decision-Making Among High‑Risk Adults: A Qualitative Study Guided by the Theoretical Domains Framework

Background and aims: Pneumococcal disease (PD) poses a substantial burden among older adults and individuals with chronic conditions, yet pneumococcal vaccination uptake remains suboptimal in Hong Kong. Understanding the psychological, social, and contextual determinants of pneumococcal vaccination decision‑making is essential for strengthening adult vaccination strategies.