Introduction | Table 1. Unintentional Injuries | Table 2. Intentional Injuries | Table 3. Leading Causes of Injury Mortality for Unintentional and Intentional Injuries | Table 4. Leading Causes of Injury Emergency Department Visits and Hospitalization for Unintentional and Intentional Injuries | Table 5. Sports and Recreation ICD-10-CA codes | Table 6. Place of Occurrence codes | Cited References | Changes Made | Acknowledgements

This document is intended to provide some suggestions on how to present and categorize injury data. It uses the ICD-10 codes from the International Statistical Classification of Diseases and Related Health Problems, 10th Revision (ICD-10), which is an international standard for reporting clinical diagnoses developed by the World Health Organization. The Canadian edition - ICD-10-CA is an enhanced version of ICD-10 developed by CIHI for morbidity classification in Canada (1).

The ICD-10-CA codes used to classify cause of injury are taken from Chapter 19 - External Causes of Morbidity and Mortality, V01-Y98 of the ICD-10-CA coding document. (The latest versions of the coding manuals are available from CIHI.) Prior to the ICD-10-CA, the external causes of morbidity and mortality were captured in the Index of External Causes of Injury or 'E' codes of ICD 9 (2). The recommended categories shown below in this document are based largely on the External Cause of Injury Matrix (3-5), and issues of recognized importance to public health. It is not mandatory that these categories are used, however, a standardized approach will facilitate comparisons among health regions.

Mechanism (or cause) and Intent of injury are the two key elements of the matrix. For public health program and policy purposes, injuries are often separated by "intent" into intentional or unintentional groupings. Intentional and unintentional injuries are not formally designated categories within the ICD10 codes. Rather, a person must select a set of codes that most likely corresponds with the intent of interest. Generally, codes V00-X64 and Y85-Y86 are considered codes for unintentional injury. Codes X65-Y09 and Y87.0 and Y87.1 are considered codes for intentional injury (which includes suicide and homicide). Please note there are other ‘intents' within the External Cause of Injury Matrix. There are two other intent categories; 1) ‘undetermined category' which includes codes such that have an event of undetermined intent, 2) Legal intervention - which includes codes of legal intervention and operations of war. There is also an extra ‘Adverse Effects' section which includes codes for complications of medical procedures and medical care and adverse drug events. These codes are not included in ‘injury' codes.

Please refer to Recommended ICD10 Groupings for Injury Core Indicators Stata syntax file.  This syntax can be used to create injury categories outlined below from data extracted from IntelliHEALTH.

Every clinical administrative data record documenting a visit for health care includes one or more diagnostic category (eg. cardiovascular disease). A person can have more than one diagnosis code for one visit. When this happens, one code is deemed ‘the most responsible diagnosis code' or main problem Dx (or MRDx is some data sources). Diagnoses that are identified as due to external causes (eg. fractured elbow) also have a companion "external cause" ICD-10-CA code. Analyses using these external cause codes are fundamental to all our public health reporting on injury. A person can have more than one external cause diagnosis for one visit. However, unlike the diagnoses codes mentioned above, external cause diagnoses do not have a main problem diagnosis in emergency (or other hospital) data. Thus, the external cause diagnoses are only included in the multi-record per visit data sources such as the Ambulatory Emergency External Cause (Chapter 20) source. Because the source has multiple records per visit, only distinct counts (# Visits (D)) can be used in order tally number of visits. IntelliHEALTH can now create crosstab tables and sum across distinct counts for external causes (Note: because the column total is a distinct count, it may be smaller than the sum of the cells within the column). For more information, please see the Report Inventory and Webinar Materials and Training sections within IntelliHEALTH.

Table 1. Unintentional Injuries 

This table provides several different categories of inintentional injury that may be important for public health.  Please note that these categories are not mutually exclusive.  Please see Tables 3 or 4 for a mutually exclusive list 'Leading Causes' of all injury - both unintentional and intentional.

 *A traffic accident is one that occurs on a public highway/road. 
**A non- traffic accident occurs in another place other than a highway/road. Although the ICD-10-CA codes uses the term 'accident', for the purposes of public health reporting, the term ‘collision' is preferred.

Assumptions made in coding decisions: 1) V02-V04 (.9) (pedestrian collision with motor vehicle) coded as traffic collisions. (5, 6, 9)  2) V39.8, V49.8...V79.8 - all motor vehicle occupant injured in other specified transport accidents are traffic. (5, 6, 9)
Note that there are no decimal places for ICD-10 codes in IntelliHEALTH, i.e., V89.2 is V892.

Table 3. Leading Causes* of Injury Mortality for unintentional and intentional injuries** 

The following table is based on Becker's et al. leading causes of death of categories (6). Please note this table provides categories that are mutually exclusive of one another.  This table provides recommendations for categories that can be reported, however health units may choose to add categories or merge categories due to small numbers depending on the specific analysis questions.

*Becker et al (6)
**Adopted from Leading Cause Groups for Mortality Tabulation found in the All-Cause Mortality Core Indicator.
‡ICD10 external cause of injury codes that are of undetermined intent, legal intervention and operations of war, and complications of medical and surgical care are not included in these leading cause categories. These codes are not included in the definitions of unintentional or intentional injury according the International External Cause of Injury Matrix (3-5).

The following table is based on Becker's et al. leading causes of death of categories (6).  Additional categories were added for analysis of emergency department visits and hospitalizations due to the fact that there are many more cases of emergency visits and hospitalizations than deaths and thus more categories can be shown.  Please note this table provides categories that are mutually exclusive of one another. This table provides recommendations for categories that can be reported, however health units may choose to add categories or merge categories due to small numbers (e.g. combine with ‘Other Unintentional Injuries') depending on the specific analysis questions.

*ICD10 external cause of injury codes that are of undetermined intent, legal intervention and operations of war, and complications of medical and surgical care are not included in these leading cause categories.  These codes are not included in the definitions of unintentional or intentional injury according the International External Cause of Injury Matrix (3-5).
Note that there are no decimal places for ICD-10 codes in IntelliHEALTH, i.e., V89.2 is V892.

The definition of sports is subjective and may be determined differently by health units and other agencies. The following codes may be considered when reporting selected sport-specific injuries.

*Inclusion of Recreational Boating in a general ‘Sports and Recreation' category is optional.  Also, it may not be known whether participation in an injury causing activity was recreational or employment related.  These suggested codes assume that all merchant and passenger ships are employment related and activities related to fishing boats, other powered watercraft etc. are recreational in nature.
**Many of the Sports and Recreation codes are only available using ICD-10-CA, as there are no corresponding codes in ICD9.

• BC Injury Research and Prevention Unit Online-Injury Surveillance Tool (7). Available from: www.injuryresearch.bc.ca
• BC Injury Research and Prevention Unit also has a section on Sports and Recreation in their Quick Facts section (8). Available from: http://www.injuryresearch.bc.ca/quick-facts/sport-recreation-leisure/

In addition to the ICD-10-CA codes listed in Table 5, Sports and Recreation data can also be obtained based on the ‘Place of Occurrence' code ‘4'.  The place of occurrence code indicator can be found in the diagnosis information tab in IntelliHEALTH. Please note that there may be a large number of patient records where place of occurrence is missing or categorized as ‘9', unspecified place.

1. Canadian Institute for Health Information [homepage on the Internet]. Toronto: Canadian Institute for Health Information; c1996-2012. ICD-10-CA; [cited 2012 Nov 13]. Available from: http://www.cihi.ca/CIHI-ext-portal/internet/en/document/standards+and+data+submission/standards/classification+and+coding/codingclass_icd10.
2. Free online searchable 2009 ICD-9-Cm codes. http://icd9cm.chrisendres.com/index.php?action=extcauses.
3. Becker R, Silvi J, Ma Fat D, L'Hours A, Laurenti R. A method for deriving leading causes of death. Bulletin of the World Health Organization. 2006;84(4):297-304 and Annex
4. Centers for Disease Control and Prevention [homepage on the Internet]. Atlanta: Centers for Disease Control and Prevention, National Center for Health Statistics.  ICD Injury Matrices; 2009 Nov 25 [2012 Nov 13]. Available from: http://www.cdc.gov/nchs/injury/injury_matrices.htm.
5. Fingerhut LA.  External cause of injury mortality matrix for ICD-10. Atlanta: Centers for Disease Control and Prevention; 2002 [cited 2012 Nov 14]. Available from: http://www.cdc.gov/nchs/data/ice/icd10_transcode.pdf.
6. State of New Jersey Department of Health [homepage on the Internet]. Trenton: State of New Jersey Department of Health. ICD-10 NJDOH External Cause of Injury. 2012 Oct 19 [cited 2012 Nov 13]. Available from: http://www4.state.nj.us/dhss-shad/query/InjuryMatrix.html.
7. BC Injury research and prevention unit [homepage on the Internet]. Vancouver: BC Injury research and prevention unit; c2012. Injury Data Online Tool; [cited 2012 Nov 13]. Available from: http://www.injuryresearch.bc.ca/
8. BC Injury Research and Prevention Unit [homepage on the Internet]. Vancouver: BC Injury research and prevention unit; c2012. Sport, Recreation, and Leisure Quick Facts; [cited 2012 Nov 13]. Available from: http://www.injuryresearch.bc.ca/quick-facts/sport-recreation-leisure/.
9. Public Health Agency of Canada.  ICD-9 - ICD10 transition matrix for external cause of injury groups. Feb. 2005 http://dsol-smed.phac-aspc.gc.ca/dsol-smed/is-sb/chirpp/ICD10-ICD9TransitionMatrixISOL.pdf