After graduating with MBChB (Honours) from the University of Glasgow, Dr. Chooi obtained the Membership of the Royal College of Physicians (UK) and subsequently the Fellowship of the Royal College of Physicians (Edinburgh). Dr Chooi underwent advanced training in the field of endocrinology at the University of Malaya Medical Centre, acquiring expertise in the management of a wide range of disorders, including patients with diabetes mellitus, thyroid disorders, osteoporosis, pituitary, gonadal and adrenal disorders as well as obesity and metabolic disorders.