ICD-11 MMS from WHO 4+

The ICD-11 is the eleventh revision of the International Classification of Diseases (ICD). It replaces the ICD-10 as the global standard for recording health information and causes of death. The ICD is developed and annually updated by the World Health Organization (WHO). Development of the ICD-11 started in 2007 and spanned over a decade of work, involving over 300 specialists from 55 countries divided into 30 work groups, with an additional 10,000 proposals from people all over the world. Following an alpha version in May 2011 and a beta draft in May 2012, a stable version of the ICD-11 was released on 18 June 2018, and officially endorsed by all WHO members during the 72nd World Health Assembly on 25 May 2019.

The ICD-11 is a large ontology consisting of about 85,000 entities, also called classes or nodes. An entity can be anything that is relevant to health care. It usually represents a disease or a pathogen, but it can also be an isolated symptom or (developmental) anomaly of the body. There are also classes for reasons for contact with health services, social circumstances of the patient, and external causes of injury or death. The ICD-11 is part of the WHO-FIC, a family of medical classifications. The WHO-FIC contains the Foundation Component, which comprises all entities of all classifications endorsed by the WHO. The Foundation is the common core from which all classifications are derived. For example, the ICD-O is a derivative classification optimized for use in oncology. The primary derivative of the Foundation is called the ICD-11 MMS, and it is this system that is commonly referred to as simply "the ICD-11". MMS stands for Mortality and Morbidity Statistics. The ICD-11 is distributed under a Creative Commons BY-ND license.

The ICD-11 officially came into effect on 1 January 2022. On 11 February, the WHO claimed that 35 countries were using the ICD-11. In the United States, an expected implementation year of 2025 has been given, but if a clinical modification is determined to be needed (similar to the ICD-10-CM), ICD-11 implementation might not begin until 2027.

The ICD-11 MMS can be viewed online on the WHO's website. Aside from this, the site offers two maintenance platforms: the ICD-11 Maintenance Platform, and the WHO-FIC Foundation Maintenance Platform. Users can submit evidence-based suggestions for the improvement of the WHO-FIC, i.e. the ICD-11, the ICF, and the ICHI.