Codes and Frequencies
For all injuries, IRECAUSNEW reports the external cause of the injury according to the International Classification of Diseases, Ninth Revision, Clinical Modification (ICD-9-CM) external cause codes, or E-codes. The E-codes are classified into different categories of injuries by the National Center for Health Statistics; these categories include: transportation, fire/burn/scald related injuries, falls, poisonings, overexertion, being struck by an object or person, an animal or insect bite, being cut or pierced, machinery-related injuries, and other injuries. See the comparability tab for information about changes in the E-codes and injury cause categories over time.
Prior to 2000, poisoning and injury episode-level data were offered by the NHIS in two separate files. For 1997-1999, "poisoning" was not available as a response category because IRECAUSNEW was only asked for injury episodes. To improve comparability across samples, IPUMS NHIS integrated all episode level data as a single record type. Episodes that were originally available in the poisoning file in 1997-1999 have been given a value of "4-Poisoning" for IRECAUSNEW. This offers more complete information on all episode-level data; however, the assignment of these episodes to the "poisoning" category was done by IHIS staff based on original data source, not based on the National Center for Health Statistics E-codes guidelines as with other categories for IRECAUSNEW. Episodes that were originally released by NHIS in the poisoning files for 1997-1999 can be identified using the variable IRPOISYN. "Poisoning" was added to the response categories for cause of injury/poisoning episodes in 2000. All cases coded as "poisoning" in 2000-forward were done are assigned based on E-codes and are classified by NCHS/NHIS staff.
In 2000 a screening question regarding the number of injuries or poisonings that were serious enough to seek medical attention was reworded and caused a marked decrease in the number of persons reporting injuries. The question was changed back to the originally intended wording in subsequent years. Despite the significant decline in the overall number of injury and poisoning episodes reported in 2000, the percentage distributions of episodes for the external cause of the injury are comparable across time.
The E-codes attributed to each category of injury vary slightly over time; for links to detailed tables illustrating which codes are included in each response category and more detailed information on the injury records, please see the User Note on Injuries and Poisonings.
- 1997-2014: All injury and poisoning episodes.
- 1997-2014 : PERWEIGHT