Functioning Section in ICD-11

Recognising the value of jointly using the ICF with the International Classification of Diseases (ICD), specifically to capture health more comprehensively and for practical uses such as for needs assessment and for reimbursement purposes [1,2], WHO has introduced a supplementary section for functioning assessment in the 11th revision of ICD (ICD-11). The use of this section by member states is optional.

Status 14.05.2018

As outlined in several publications [3,4], the idea of including some functioning information in ICD-11 is not new. What is new, however, is that there is a designated section (V-chapter) that contains 46 codes for specific functioning entities. WHO indicated that these codes were developed upon consideration of ICF's "Annex 9: Suggested ICF data requirements for ideal and minimal health information systems or surveys", the WHO Disability Assessment Scale 2.0 (WHODAS 2.0), and the functioning module of the Model Disability Survey (MDS). The majority of these functioning entities mirror the wording of specific ICF categories. For example, the ICD-11 code VB20 Mobility of joint functions mirrors the ICF category b710 Mobility of joint functions. There are, however, other ICD-11 functioning codes that are not equivalent to a specific ICF category. For example, the ICD-11 code VA20 Voice and speech functions is equivalent to the whole ICF chapter b3 Voice and speech functions rather than any specific code under this body functions chapter. There are also four ICD-11 codes that correspond to a block of ICF categories, e.g. VC03 Carrying, moving and handling objects covered by the ICF block d430-d449 Carrying, moving and handling objects.

Also new is the notion, as suggested by WHO in the ICD-11 Reference Guide, of using these functioning codes to generate a summary functioning score based on assessment of the individual. WHO does emphasise that the ICF itself should be employed for full functioning reporting.

WHO is calling on WHO-FIC collaborating centres to field test the functioning section along with the whole ICD-11. Organisations interested in conducting pilot studies to showcase the feasibility of using the functioning entities, for example in disability assessment, should contact the WHO-FIC collaborating centre in their country or regions. The list of WHO-FIC collaborating centres can be found here:

  1. Stucki G, Bickenbach J. Functioning: the third health indicator in the health system and the key indicator for rehabilitation. Eur J Phys Rehabil Med. 2017;53(1):134-8.
  2. Escorpizo R, Kostanjsek N, Kennedy C, Nicol MM, Stucki G, Ustün TB. Harmonizing WHO's ICD and ICF: importance and methods to link disease and functioning. BMC Public Health. 2013;13:742.
  3. Selb M, Kohler F, Robinson Nicol MM, Riberto M, Stucki G, Kennedy C, Üstün B. ICD-11: A comprehensive picture of health, an update on the ICD–ICF joint use initiative. J Rehabil Med. 2015;47(1):2-8.