This topic refers to the process of translating causes of death from death certificates into standardised codes using systems like ICD-10 or ICD-11. This ensures consistency in health data reporting, enabling accurate analysis of mortality trends across populations and time. It's a vital tool for public health planning and global disease surveillance.

In mortality coding, the General Principle and 3 Selection Rules are guidelines used to identify the underlying cause of death from multiple conditions listed on a death certificate. These rules ensure consistency and accuracy in coding across different cases and countries.

Modification Rules are applied when the standard selection rules (General Principle and 3 Selection Rules) don’t lead to a clear or medically logical underlying cause of death. These rules help adjust or “modify” the selection to ensure consistency and accuracy.