Introduction
Variable-axis structure and special-group priority
ICD is a variable-axis classification: conditions are grouped so they are convenient for epidemiological study, not by anatomical site alone.
What this means in practice
- Four chapters are 'special groups': Chapter I (infectious and parasitic diseases, A00-B99), Chapter XV (pregnancy, childbirth and the puerperium, O00-O99), Chapter XVI (perinatal conditions, P00-P96) and Chapter XIX (injury, poisoning and external causes, S00-T98).
- Where there is doubt about which chapter a condition belongs to, the special-group chapter takes priority over the body-system chapter. The excludes notes at the head of each chapter enforce this.
- This is why clicking one organ in the explorer cannot return a single chapter of codes: a lung yields malignancy (C34.-), infection (J18.-), occupational disease (J60-J65) and trauma (S27.-) at once.
Where the explorer applies it
neoplasminflammatorytrauma
Source and licensing.
Summaries below are original text written for this product and point to the named CIHI standard; they are not a reproduction of it. CIHI content may be reproduced unaltered for non-commercial purposes with attribution - commercial reproduction requires CIHI's prior written authorization.
Canadian Institute for Health Information. Canadian Coding Standards for Version 2022 ICD-10-CA and CCI. Ottawa, ON: CIHI; 2022. CIHI codes and classifications
Canadian Institute for Health Information. Canadian Coding Standards for Version 2022 ICD-10-CA and CCI. Ottawa, ON: CIHI; 2022. CIHI codes and classifications