Dr David Sia graduated from the Faculty of Medicine, National University of Singapore in 2005. In his early years as a junior doctor, he gained clinical experience in various departments before commencing his Basic Specialist Training in Diagnostic Radiology in 2009. He obtained the Fellowship of the Royal College of Radiologists (UK) and Master of Medicine Diagnostic Radiology (Singapore) in 2012, being conferred the inaugural Peh Eng Teck Memorial medal. Subsequently, he pursued his Advanced Specialist Training in various hospitals with a special interest in Musculoskeletal Radiology.

In 2015, he was awarded HMDP fellowship and spent six months as a clinical fellow in the Hospital for Special Surgery, New York, at one of the renowned orthopedic imaging departments in North America. During his fellowship, he had the opportunity to learn the most advanced and updated imaging techniques in musculoskeletal radiology, as well as participate in teaching and research activities.

Upon returning to Singapore, he was appointed the Program Director of NUHS Diagnostic Radiology residency programme, a post he served for three years. Together with the teaching faculty in NUHS, he was instrumental in mentoring aspiring trainee doctors and coaching many of them to become qualified competent radiologists. He was also a clinical tutor at the Yong Loo Lin School of Medicine, NUS.