WHO ICD-11 REFERENCE
ICD-11 Mental, Behavioural and Neurodevelopmental Disorders
A plain-English, non-diagnostic directory based on the WHO ICD-11 classification and its Clinical Descriptions and Diagnostic Requirements.
Reviewed against WHO ICD-11 resources on 24 August 2026
What ICD-11 is
ICD-11 is the World Health Organization’s global classification for recording and reporting diseases and health-related conditions. The 2024 Clinical Descriptions and Diagnostic Requirements support qualified professionals in identifying mental, behavioural and neurodevelopmental disorders. They are not designed as a self-diagnosis checklist.
Classification directory
How to read the condition pages
Each page describes the broad clinical idea, features a qualified professional may explore, important differential questions and the responsible UK route. The text paraphrases the classification and does not reproduce WHO diagnostic requirements. Exact coding, exclusions, qualifiers and boundaries should be checked in the current WHO browser by a trained professional.
Important classification boundaries
- A symptom is not automatically a disorder; duration, distress, impairment, context and exclusions matter.
- Culture, age, development, disability, trauma and life stage can change presentation and interpretation.
- Physical illness, medicines, sleep and substances can mimic or contribute to mental-health symptoms.
- Gender incongruence is not classified as a mental disorder in ICD-11.
- Sleep-wake disorders sit in a separate ICD-11 chapter but are included here as a relevant linked pathway.
Official WHO sources
Scope, safety and urgent help
iMetaWellness provides complementary wellbeing information and reflective support. It does not diagnose a mental disorder, select investigations, interpret results as a medical opinion, prescribe treatment or replace a GP, psychiatrist, psychologist, pharmacist or NHS service. A test is useful only when a qualified professional has a clear question and a plan for acting on the result.
If someone may act on suicidal thoughts, cannot remain safe, has severe confusion, new psychosis, collapse, seizure, chest pain or another immediate danger, call 999 or attend A&E. For urgent concerns that are not immediately life-threatening, contact NHS 111, the person’s GP, mental-health team or local crisis service.
Use this information in a responsible next step
We can help you organise observations, questions, routines and a concise summary for an appropriate professional. We do not order tests or confirm diagnoses.
