Development of the Traditional Medicine Classification Module 1 in ICD-11

The 11th revision of the International Classification of Diseases (ICD-11) introduced, for the first time in its history, a chapter dedicated to traditional medicine (TM). This inclusion represents a major step toward the international recognition and standardization of TM concepts and terminologies. This article reviews the background, development process, and significance of incorporating the TM chapter into ICD-11, and discusses future directions for its utilization in health information systems, research, and education. The development of the ICD-11 TM chapter began in 2005 under the WHO Western Pacific Regional Office as part of a standardization project for traditional East Asian medicine. It was transferred to WHO headquarters in 2009, reviewed by 142 experts from 22 countries, and field-tested in Japan, China, Korea, and the United Kingdom. The WHO General Assembly adopted ICD-11 in 2019, and Chapter 26—Traditional Medicine Conditions Module 1—came into effect in January 2022. The inclusion of TM does not imply WHO endorsement of its efficacy or safety, but rather provides a global platform for evidence-based evaluation through research and statistical analysis. Following Module 1, Module 2—covering Ayurveda, Unani, and Siddha—was released in 2025. The establishment of the Traditional Medicine Reference Group (TMRG) within WHO Family of International Classification (WHO-FIC) further facilitates integration of TM concepts into the International Classification of Health Interventions (ICHI). The ICD-11 TM chapter provides an essential global framework for TM research, education, and policy, fostering international collaboration toward evidence-based integration of traditional medicine into health systems. Traditional Medicine Classification, WHO ICD-11 • ICD-11 includes, for the first time, a chapter dedicated to traditional medicine (TM). • The TM chapter was developed through international collaboration led by WHO and WPRO. • It provides a global framework for research, education, and health information systems. • The inclusion supports evidence-based evaluation of TM through global data collection. • Module 2 (Ayurveda, Unani, Siddha) and continued maintenance expand TM’s international reach.