Query purpose:
The purpose of the CDC Pedestrian Motor Vehicle Traffic Injury v1 syndrome definition is to assist with detection of initial emergency department (ED) visits among pedestrians unintentionally injured on public roads in traffic-related crashes involving a motor vehicle. The syndrome definition can be used to monitor trends and might help identify situations and populations that could be well served by specific injury prevention strategies.
Definition description:
The CDC Pedestrian Motor Vehicle Traffic Injury v1 syndrome definition aims to identify emergency department visits involving pedestrians unintentionally injured on a public road in a crash involving a motor vehicle.
For this syndrome definition:
Pedestrian definition: A pedestrian is defined as any person
- on foot,
- walking,
- running,
- jogging
- sitting or lying down,
- in a motorized or non-motorized wheelchair,
- in a baby carriage,
- on roller skates or inline skates,
- on a skateboard,
- on a non-motorized scooter,
- on a motorized mobility scooter designed to accommodate disability, or
- on skis, sleds, or ice skates.
Motor vehicle definition: A motor vehicle includes cars, pick-up trucks, vans, SUVs, heavy transport vehicles (i.e., tractor-trailers), buses, 2-wheeled vehicles (i.e., motorcycles), and 3-wheeled vehicles (i.e., 3-wheeled motorcycles).
Public road definition: A public road is defined as any road under the jurisdiction of and maintained by a public authority and open to public travel.
Timing: The syndrome definition aims to detect initial emergency department visits that could include visits among pedestrians injured in a crash that occurred minutes, hours, days, or weeks earlier.
Types of ED visits the syndrome definition excludes:
- visits among people injured while using micro-mobility devices (e.g., e-scooters) and bicycles;
- visits among pedestrians injured in a collision with any conveyance that is not a motor vehicle (e.g., pedestrian hit by bicycle or e-scooter);
- visits due to motor vehicle crashes that occur in driveways, parking lots, and private roads (e.g., roads on industrial premises, farms, and roads in private communities);
- visits caused by motor vehicle crashes that are violence- or suicide-related; and
- subsequent or sequela visits for the initial traffic-related crash.
How it was developed: Syndrome definition development was a collaboration among scientists from the Centers for Disease Control and Prevention’s National Syndromic Surveillance Program; Division of Injury Prevention; Division of Nutrition, Physical Activity, and Obesity; and state and local health departments.
Syndrome definition development included identifying relevant discharge diagnoses and chief complaint keywords.
Discharge diagnoses:
First, International Classification of Diseases, 9th and 10th Revisions, Clinical Modification codes (ICD-9-CM and ICD-10-CM), were identified as potential discharge diagnosis codes. To identify appropriate ICD-9-CM and ICD-10-CM codes for pedestrian motor vehicle traffic injuries, the team reviewed and considered codes currently used or recommended for pedestrian injury surveillance. These included (but were not limited to) codes used in surveillance by the National Highway Traffic Safety Administration, by the Centers for Disease Control and Prevention, and recommended in the Consensus Recommendations for Pedestrian Injury Surveillance by the Safe States Alliance. Examples of these potential pedestrian injury codes can be found here:
- https://crashstats.nhtsa.dot.gov/Api/Public/ViewPublication/813310
- https://www.cdc.gov/nchs/data/ice/icd10_transcode.pdf
- https://pedevalguide.safestates.org/wp-content/uploads/2020/07/Consensus-Recommendations-for-Pedestrian-Injury-Surveillance-ISW8.pdf
The ICD-9-CM and ICD-10-CM codes chosen for the syndrome definition align with how the Centers for Disease Control and Prevention defines pedestrian injury in their surveillance systems for fatal and nonfatal injury (https://www.cdc.gov/injury/wisqars/index.html), which are also similar to the Safe States Alliance’s recommendations. The National Highway Traffic Safety Administration currently uses a narrower definition of pedestrian (i.e., any person on foot, walking, running, jogging, sitting, or lying down) than this syndrome definition.
ICD-10-CM codes chosen for the syndrome definition can differentiate between pedestrians injured while on foot, on roller blades or inline skates, on skateboards, or on other conveyance. Several types of pedestrians are grouped into the “other conveyance” category, including people using wheelchairs or motorized mobility scooters designed to accommodate disability, babies in strollers, and people on skis, sleds, ice skates, or non-motorized scooters.
Second, several team members independently searched for relevant SNOMED codes (https://browser.ihtsdotools.org/?perspective=full&conceptId1=214391003&edition=MAIN/2022-10-31&release=&languages=en) using keywords (e.g., pedestrian). Selected SNOMED codes were collaboratively reviewed for final inclusion based on relevance to the team’s pedestrian injury definition.
Chief complaint keywords:
First, the team used the ESSENCE text analysis function to generate common words used in chief complaints for emergency department visits that involved the previously selected ICD-9-CM and ICD-10-CM codes. Words with the highest frequency of occurrence in visits were identified and selected based on relevance to the syndrome definition (e.g., “a” was not relevant, but “pedestrian” was).
Second, queries using the chief complaint field for each keyword term(s) selected were conducted, and three CDC team members independently reviewed 100 randomly selected visits from 2021 for each query to determine the positive predictive value of the visits. After each query review, findings from the three team members were compared, interrater reliability was calculated, improved keywords were created, and then the query was run again. This process was iteratively repeated until selected keywords and keyword pairings generated visits with high positive predictive values and interrater reliability (e.g., both ≥90%).
Exclusion discharge diagnosis codes and chief complaint keywords:
The CDC team identified ICD-9-CM and ICD-10-CM codes and chief complaint keywords corresponding to pedestrian-related ED visits that should be excluded by the syndrome definition. For example, the ICD-10-CM code V03.13, which represents a diagnosis for a person injured while using a micro-mobility conveyance (e.g., e-scooter), was listed as an exclusion discharge diagnosis code. ICD-10-CM codes and chief complaint keywords related to non-traffic-related crashes (e.g., occurring in private driveway or residence) and assault or self-harm related crashes were also excluded. Additionally, the syndrome definition aims to exclude visits where the pedestrian injury occurred “months ago,” “years ago,” or “last year” but otherwise, does not address the timing between the injury and the initial visit.
How it works:
The Chief Complaint Discharge Diagnosis (CCDD) field is used to query both the discharge diagnosis codes and chief complaint free text, with exclusions, to identify emergency department visits.
The syndrome definition identifies any visit with chief complaint keyword(s) or discharge diagnosis code(s) indicating visits involving pedestrians unintentionally injured on a public road in a crash involving a motor vehicle (see Table 1, “inclusions”). Visits must not include certain chief complaint keyword(s) or discharge diagnosis code(s) (see Table 1, “exclusions”).
For consideration:
This syndrome definition has limitations, including:
- Some false positive visits may be detected, though infrequently, by the syndrome definition.
- Queries for earlier time periods when ICD-9-CM codes were predominantly used (i.e., 2015 and earlier) will not be directly comparable to queries for later years because ICD-9-CM codes do not distinguish between initial emergency department visit encounters and subsequent or sequela visits.
(,(,(,^struck by car^,or,^struck by a car^,or,^struck by vehicle^,or,^struck by a vehicle^,or,^struck by bus^,or,^struck by a bus^,or,^hit by car^,or,^hit by a car^,or,^hit by vehicle^,or,^hit by a vehicle^,or,^hit by bus^,or,^hit by a bus^,),AND,(,!ped!,or,^pedestrian^,or,!pt!,or,^patient^,),),or,(,(,^got r[au]n over^,or,^r[au]n over by^,),AND,(,!ped!,or,^pedestrian^,or,!pt!,or,^patient^,),AND,(,^vehicle^,or,!car!,or,!bus!,),),OR,(,^ped vs car^,or,^pedestrian vs car^,or,^ped vss car^,or,^pedestrian vss car^,or,^ped versus car^,or,^pedestrian versus car^,or,^car[- ]ped^,or,^car vs ped^,or,^car vss ped^,or,^car versus ped^,or,^ ped[- ]car^,or,^ped vs bus^,or,^pedestrian vs bus^,or,^ped vss bus^,or,^pedestrian vss bus^,or,^ped versus bus^,or,^pedestrian versus bus^,or,^bus[- ]ped^,or,^bus vs ped^,or,^bus vss ped^,or,^bus versus ped^,or,^ ped[- ]bus^,or,^ped vs vehicle^,or,^pedestrian vs vehicle^,or,^ped vss vehicle^,or,^pedestrian vss vehicle^,or,^ped versus vehicle^,or,^pedestrian versus vehicle^,or,^vehicle[- ]ped^,or,^vehicle vs ped^,or,^vehicle vss ped^,or,^vehicle versus ped^,or,^ ped[- ]vehicle^,or,^ped vs auto^,or,^pedestrian vs auto^,or,^ped vss auto^,or,^pedestrian vss auto^,or,^ped versus auto^,or,^pedestrian versus auto^,or,^pedestrian struck^,or,^auto[- ]ped^,or,^auto vs ped^,or,^auto vss ped^,or,^auto versus ped^,or,^ ped[- ]auto^,or,^ped vs mv^,or,^pedestrian vs mv^,or,^ped vss mv^,or,^pedestrian vss mv^,or,^ped versus mv^,or,^pedestrian versus mv^,or,^ped vs motor vehicle^,or,^pedestrian vs motor vehicle^,or,^ped vss motor vehicle^,or,^pedestrian vss motor vehicle^,or,^ped versus motor vehicle^,or,^pedestrian versus motor vehicle^,or,^motor vehicle[- ]ped^,or,^mv vs ped^,or,^mv vss ped^,or,^mv versus ped^,or,^mv[- ]ped^,or,^mvc vs ped^,or,^mvc vss ped^,or,^mvc versus ped^,or,^mvc[- ]ped^,or,^ ped[- ]mv^,or,^motor vehicle vs ped^,or,^motor vehicle vss ped^,or,^motor vehicle versus ped^,or,^ ped[- ]motor vehicle^,or,^motor vehicle crash vs ped^,or,^motor vehicle crash vss ped^,or,^motor vehicle crash versus ped^,or,^motor vehicle crash[- ]ped^,or,^motor vehicle collision vs ped^,or,^motor vehicle collision vss ped^,or,^motor vehicle collision versus ped^,or,^motor vehicle collision[- ]ped^,or,^his electric scooter^,or,^her electric scooter^,),OR,(,^[;/ ]V0[234].[19][0129][X0-9]A^,or,^[;/ ]V0[234][19][0129][X0-9]A^,or,^[;/ ]V09.2[019][X0-9]A^,or,^[;/ ]V092[019][X0-9]A^,or,^[;/ ]V09.3[X0-9][X0-9]A^,or,^[;/ ]V093[X0-9][X0-9]A^,or,^[;/ ]E81[0-9].7^,or,^[;/ ]E81[0-9]7^,or,^[;/ ]214089004^,or,^[;/ ]214101002^,or,^[;/ ]214112002^,or,^[;/ ]214123003^,or,^[;/ ]214134000^,or,^[;/ ]214215006^,or,^[;/ ]214227009^,or,^[;/ ]214230002^,or,^[;/ ]214397004^,or,^[;/ ]32906002^,),),ANDNOT,(,^[;/ ]V[1-7][0-9]^,or,^[;/ ]V8[0-6]^,or,^[;/ ]V87.[0-6]^,or,^[;/ ]V87[0-6]^,or,^[;/ ]V87.[8-9]^,or,^[;/ ]V87[8-9]^,or,^[;/ ]V89.[0139]^,or,^[;/ ]V89[0139]^,or,^[;/ ]V9[X0-9]^,or,^[;/ ]V0[01]^,or,^[;/ ]V0[234].0[01239]^,or,^[;/ ]V0[234]0[01239]^,or,^[;/ ]V0[234].[19]3^,or,^[;/ ]V0[234][19]3^,or,^[;/ ]V0[56]^,or,^[;/ ]V09.[01]^,or,^[;/ ]V09[01]^,or,^[;/ ]X8[123]^,or,^[;/ ]Y0[23]^,or,^[;/ ]Y3[123]^,or,^[;/ ]Y92.009^,or,^[;/ ]Y92009^,or,^[;/ ]Y92.01[45]^,or,^[;/ ]Y9201[45]^,or,^[;/ ]Y92.194^,or,^[;/ ]Y92194^,or,^[;/ ]Y92.481^,or,^[;/ ]Y92481^,or,^[;/ ]Y92.838^,or,^[;/ ]Y92838^,or,^[;/ ]Y92.524^,or,^[;/ ]Y92524^,or,^[;/ ]Y92.008^,or,^[;/ ]Y92008^,or,^[;/ ]Y93.55^,or,^[;/ ]Y9355^,or,^[;/ ]R45.85^,or,^[;/ ]R4585^,or,^motorcyclist^,or,^motorcycle^,or,^moped^,or,^mo-ped^,or,^parking lot^,or,^driveway^,or,^parking spot^,or,^e-scooter^,or,^escooter^,or,^e scooter^,or,^a electric scooter^,or,^an electric scooter^,or,^bicycle^,or,^bike^,or,^bicycling^,or,^cyclist^,or,^months ago^,or,^months prior^,or,^mos ago^,or,^mos prior^,or,^years ago^,or,^year ago^,or,^years prior^,or,^year prior^,or,^yrs ago^,or,^last year^,or,^assault^,or,^battery^,or,^car jack^,or,^theft^,or,^trying to get hit^,or,^tried to get hit^,or,^try to get hit^,or,^plan to get hit^,or,^mental health^,or,^suicidal^,or,^suicide^,or,^almost hit^,or,^almost been hit^,or,^was not hit^,or,^driver^,or,^passenger^,or,^flipped^,or,^stopped^,or,^tipped^,or,^tripped^,or,^dropped^,or,^ cart ^,or,^hit by the car door^,or,^hit by a car door^,or,^hit by car door^,or,^struck by car door^,or,^struck by a car door^,or,^private residence^,or,^on the bus^,or,^on a bus^,)