Development of an AI chatbot to support shared decision-making in rheumatoid arthritis: a two-phase usability study. - Se Rim Choi; Seongjun Yoon; Soo-Bin Lee; Ha Rim Park; Hye-Rin Ko; Yu-Seon Jung; Eunwoo Nam; Soo-Kyung Cho; Yoon-Kyoung Sung (BMC Medical Informatics Decis. Mak., 2026)