DIFFERNCE BETWEEN ICD 10 AND ICD 11

WHO recently already released ICD 11th edition and will come into effect on Jan 01, 2022. Let’s all not come into panic mode and note that so far the USA is not sure about when they’ll be ready to implement ICD 11 so far, but still, we cannot say anything.

Let’s see the Difference between the ICD 10 and the ICD 11 Coding systems. The ICD-11 MMS is the primary derivative of the Foundation Component, and that is commonly referred to and recognized as "ICD-11 MMS. The abbreviation is variously written with or without a hyphen between 11 and MMS. 

• MMS stands for Mortality and Morbidity Statistics.
• These codes are a minimum of 4 character codes in ICD 11 and 2 levels of subcategories.
• The chapter numbering of ICD 11 is Arabic numbers, not Roman numbers

ICD 10 represents 14400 diagnosis but ICD 11 has 55,000 unique codes to represent the comprehensive list of diagnosis. Changing the number of items in the ICD is considered extremely useful because it allows researchers and health care organizers to have a more complete picture. 

For example, in ICD-11 all types of diabetes and other conditions are described in detail

There is major codes structural difference between ICD 10 and ICD 11. ICD-11 changes the 3- character category codes (the characters to the left of the decimal) to four with an alpha-character in the second position and a number always in the third position. 

So the coding scheme always has a letter in the second position to differentiate from the codes of ICD-10 For example, 1A00

In the ICD-10, every code starts with a letter, indicating the chapter. The first character of code always relates to the chapter. Numbers 1-9 are used for the first nine chapters and letters are used for chapters 10 to 26. A letter is always in the 2nd position to differentiate from ICD-10 codes.

• No more “I” and “O” in ICD MMS to avoid confusion between “1” and “0” in ICD 11.
• Residual categories use Y for other, Z for Other Specified, and unspecified Category. 

For Example

• 1C4Y – Other Specified Bacterial Disease and 1C4Z - Unspecified Bacterial Disease.

Below is the list of ICD 11 MMS Chapters

1. A00–1H0Z Certain infectious or parasitic diseases
2. A00–2F9Z Neoplasms
3. A00–3C0Z Diseases of the blood or blood-forming organs
4. A00–4B4Z Diseases of the immune system
5. A00–5D46 Endocrine, nutritional or metabolic diseases
6. A00–6E8Z Mental, behavioral or neurodevelopmental disorders
7. A00–7B2Z Sleep-wake disorders
8. A00–8E7Z Diseases of the nervous system
9. A00–9E1Z Diseases of the visual system
10. AA00–AC0Z Diseases of the ear or mastoid process
11. BA00–BE2Z Diseases of the circulatory system
12. CA00–CB7Z Diseases of the respiratory system
13. DA00–DE2Z Diseases of the digestive system
14. EA00–EM0Z Diseases of the skin 
15. FA00–FC0Z Diseases of the musculoskeletal system or connective tissue
16. GA00–GC8Z Diseases of the genitourinary system
17. HA00–HA8Z Conditions related to sexual health
18. JA00–JB6Z Pregnancy, childbirth or the puerperium
19. KA00–KD5Z Certain conditions originating in the perinatal period
20. LA00–LD9Z Developmental anomalies
21. MA00–MH2Y Symptoms, signs or clinical findings, not elsewhere classified
22. NA00–NF2Z Injury, poisoning or certain other consequences of external causes
23. PA00–PL2Z External causes of morbidity or mortality
24. QA00–QF4Z Factors influencing health status or contact with health services
25. RA00–RA26 Codes for special purposes
26. SA00–SJ3Z Supplementary Chapter Traditional Medicine Conditions - Module I
27. VA00–VC50 Supplementary section for functioning assessment
28. X...–X... Extension Codes

With the addition of New Chapters related to Disorders of the Immune system, Diseases of the blood and blood-forming organs, Conditions related to sexual health, and Sleep-Wake Disorder, Extension codes, Traditional medicine in ICD 11 represents the more complex diagnosis. 

For example delayed sleep-wake phase disorder (7A60), advanced sleep-wake phase disorder (7A61), Irregular sleep-wake rhythm disorder (7A62)

• Skin Ca type – Basalioma was missing in ICD 10, so added in ICD 11. 

So many new conditions Compulsive sexual behavior disorder, Body integrity dysphoria, Gaming disorder categorized in mental, behavioral, and neurodevelopmental disorders. MBND contains 21 disorder groupings compared with 11 disorder groupings in ICD-10.

In below list of each disorder added into the ICD 11 list under Mental Health Disorders

• Anxiety or fear-related disorders
• Catatonia
• Disorders of bodily distress or bodily experience
• Disorders due to substance use or addictive behaviors
• Disorders specifically associated with stress
• Disruptive behavior or dissocial disorders
• Dissociative disorders
• Elimination disorders
• Factitious disorders
• Feeding or eating disorders
• Impulse control disorders
• Mental or behavioral disorders associated with pregnancy, childbirth, and the puerperium
• Mood disorders
• Neurocognitive disorders
• Neurodevelopmental disorders
• Obsessive-compulsive or related disorders
• Paraphilic disorders
• Personality disorders and related traits
• Schizophrenia or other primary psychotic disorders

Please note that ICD-11 is only for diagnosis coding and ICD-10-PCS is completely separate from ICD-10 and will not be updated with the transition of ICD-10 to ICD-11. ICD-10-PCS is not a WHO-developed or maintained vocabulary. ICD-10-PCS is a procedure classification system designed by CMS for coding hospital-based procedures.