With patient decision aids (PDAs) to evaluate all available care options and weigh patients' preferences against evidence-based medicine, medical personnel and patients can make health-related decisions together. However, little research has been conducted on the critical determinants of medical personnel's intentions to share knowledge with one another within their organization to develop PDAs. This study has developed a socio-technical integrated model to explain medical personnel's intentions to share knowledge for the development of PDAs. This study employed a field survey in Taiwan to collect data. 421 valid questionnaires were completed for the statistical analysis. The results indicate that social network, social trust, perceived usefulness, compatibility, result demonstrability, and image have positive effects on knowledge-sharing intentions. Social network has a positive influence on shared goals, and ease of use has a positive impact on perceived usefulness. These findings provide valuable insights for medical informatics practices in promoting shared medical decision making.