Tools & Resources
... for coding and verification
International Classification of Health Interventions (ICHI)
The official WHO browser for the complete ICHI classification. Browse all Action, Target and Means axis elements, view pre-coordinated stem codes, and explore the full hierarchy of health intervention categories.
Open ICHI Browser ↗ICHI Reference Guide
The official coding rules and guidelines published by the WHO. The Reference Guide defines how Action, Target and Means elements may be combined, how extension codes are applied, and how post-coordinated codes are constructed. This is the authoritative rule set that CodAs follows for every coding request.
Download Reference Guide (PDF) ↗ICHI Code Verification
An independent verification tool for WHO ICHI pre-coordinated stem codes. Enter any stem code generated by CodAs to confirm it exists in the official dataset.
Every coding result from CodAs includes a direct verification link. Click it to open this tool with the stem code pre-filled – or paste any code manually to check its validity.
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