Extension Codes

Definition

!markdown Extension codes should never be used in primary classification coding or tabulation. - They are provided for use as supplementary or additional codes when desired to identify more detail in statistical categories classified elsewhere. - Extension codes may be used alone in other contexts.

14 subordinate codes

• Severity Scale Value
• Temporality
• Aetiology
• Topology Scale Value
• Anatomy and topography
• Histopathology
• Dimensions of injury
• Dimensions of external causes
• Consciousness
• Substances
• Diagnosis code descriptors
• Capacity or context
• Health Devices, Equipment and Supplies
• Extension codes of particular relevance to skin diseases