Dr Yamaoka is Professor and Chairman of the Department of Rheumatology and Infectious Diseases, Kitasato University School of Medicine, Sagamihara, Tokyo, Japan and is board certified in internal medicine and rheumatology. He completed his medical training at the University of Occupational and Environmental Health, Kitakyushu, Japan in 1993 followed by residencies in internal medicine at the Matsuyama Red Cross Hospital, Matsuyama, Japan, Kyushu University Hospital, Fukuoka, Japan and Saiseikai Karatsu Hospital, Karatsu, Japan between 1993 and 1995. Dr Yamaoka was a research fellow at Kyushu University School of Medicine, Fukuoka, Japan from 1995 to 1999. He received his PhD from Kyushu University School of Medicine in 2001 and was a visiting fellow at the National Institute of Arthritis and Musculoskeletal and Skin Diseases at the National Institutes of Health, Bethesda, MD from 2001 to 2005.

Dr Yamaoka is a member of numerous national Japanese and international academic societies. He is a council member for the Japan College of Rheumatology and The Japanese Society of Clinical Immunology, and an international fellow of the American College of Rheumatology. Dr Yamaoka currently serves as an editorial board member and transmitting editor for Modern Rheumatology Case Reports, an editorial board member and associate editor for Frontiers in Immunology, an associate editor for Cytokine and as an editor for Inflammation.