Injury Data and NCHSInjury Data and NCHS

U.S. DEPARTMENT OF HEALTH AND HUMAN SERVICESCenters for Disease Control and PreventionNational Center for Health Statistics

Lois A. FingerhutLois A. FingerhutNCIPC Conference, May 2005NCIPC Conference, May 2005

Focus for this morningFocus for this morning

• NCHS injury-related web pages

• ICD-9 to ICD-10 comparability file

• Frameworks for presenting data

• Poisoning- a recent example of a question of definition

• Injury severity- new collaborative work

Our new injury website Our new injury website pagespages

• One stop shopping for questions/presentations/publications regarding NCHS surveys and data sets that have an injury component

• Links to non-NCHS sources (eg WISQARS)

• Up-to-date information on the International Collaborative Effort (ICE) on Injury Statistics

http://www.cdc.gov/

Injury Mortality DataFrom the National Vital Statistics System

Data Source | Mortality-Injury Summary | Injury Death Codes

Publications |Presentations |Tabulated Data |Public Use Data

 Data Tools | Query Systems | Related Links

                  National Databases

ICD-9 to ICD-10 Comparability

• A Guide to State implementation of ICD-10 for mortality ( 2000)

• Comparability reports going back to ICD-4 to ICD-5

• ICD-9 t o ICD-10 detail

• Downloadable file on ICD-9 to ICD-10 comparability study

• Full file documentation

• SAS statements

http://www.cdc.gov/nchs/datawh/statab/unpubd/comp.htm#A%20guide%20to%20state%20implementation%20of%20ICD-10

ICD-10 on the WHO WebsiteICD-10 on the WHO Website

• WHO Family of International Classifications

• http://www.who.int/classifications/en/

•There is a complete online version of ICD-10

Frameworks for presenting Frameworks for presenting datadata

Frameworks for presenting Frameworks for presenting datadata

• External causes

•ICD-9 and ICD-9 CM external cause code matrices

• ICD-10 external cause code matrix

• Injury Diagnoses

•ICD-9 CM Diagnosis codes: Barell Matrix

•ICD-10 injury diagnosis code matrix

External cause matrix-basic External cause matrix-basic structurestructure

Intent of injury

Mechanism Unintentional

Suicide

Homicide Undeter-mined

Other

MV-traffic

Cut

Firearm ICD-9, ICD-9-CM and ICD-10 External cause codes

Poisoning

Struck by/

against

Suffocation

Etc…..

External Cause of Injury Mortality External Cause of Injury Mortality Matrix (ICD-10)Matrix (ICD-10)

0

5,000

10,000

15,000

20,000

25,000

30,000

35,000

40,000

45,000

50,000

MotorVehicleTraffic

Firearm Poisoning Falls Suffocation Drowning

Selected Mechanisms of injury

Number of deaths

Unintentional Self-harm Assault Undetermined Legal int/other

Injury deaths by matrix: 2002Injury deaths by matrix: 2002

New International New International Recognition!Recognition!

• The Mortality Reference Group (MRG), the group charged with refining and recommending changes to the ICD formally recommended

“Publish External Cause of Injury Mortality Matrix data in addition to standard WHO tabulations to facilitate statistical analysis”

Source: www.who.int/classifications/network/en/icelandexecutifsummary.pdf

Nature of injury Fractures Internal Open Sprains Burns Dislocationwounds & Strains

Site of injuryHead and NeckTraumatic Brain Injury

specific sites

Spinal Cord Injuryspecific sites

Vertebral Column Injuryspecific sites

Torsospecific sites

Extremitiesspecific sites

SYSTEM WIDE

Barell Matrix-basic structureBarell Matrix-basic structure

ICD-9 CM codes

Barell matrix: a standard for Barell matrix: a standard for presenting injury morbidity datapresenting injury morbidity data

• See ICE webpage for full description of the matrix• www.cdc.gov/nchs/about/otheract/ice/barellmatrix.htm

• Barell V, Aharonson-Daniel L, Fingerhut LA, MacKenzie EJ, et al. An introduction to the Barell body region by nature of injury diagnosis matrix. • Injury Prevention 2002;8:91-6.

• National Hospital Discharge Survey: 2002 Annual Summary With Detailed Diagnosis and Procedure Data (table 24)

• www.cdc.gov/nchs/data/series/sr_13/sr13_158.pdf

Nature of injury Fractures Internal Open Amputations Burns Dislocation Bloodorgan wounds vessel

Body region of injuryHead and NeckTraumatic Brain Injury

specific sites

Spine and Upper backspecific sites

Torsospecific sites

Extremitiesspecific sites

Unclassifiable by reionSYSTEM WIDE

ICD-10 Injury Mortality ICD-10 Injury Mortality Diagnosis MatrixDiagnosis Matrix

ICD-10 ‘S’ & ‘T’ codes

Head and neck allTraumatic brain injuryOther headNeckHead and Neck

Spine and upper backSpinal cordVertebral column

TorsoThorax AbdomenPelvis and lower backAbdomen, lower back & pelvisTrunk, other

ExtremitiesUpper extremitiesHipOther lower extremities

Not classifiable by siteMultiple body regionsSystem wideUnspecified

ICD-10 Body regionof injury categoriesfor mortality

Level 1

Level 2

Additional detail is available, butAdditional detail is available, butnot necessarily appropriate for not necessarily appropriate for

mortalitymortality

• For example, Level 2- ‘Other lower extremities’ can be disaggregated to Level 3 categories

• Thigh L3-31• Hip & Thigh L3-32• Upper Leg and thigh L3-33• Knee L3-34• Lower leg L3-35• Foot L3-36• Ankle L3-37• Other and multiple ankle and foot L3-38• Toes L3-39• Other lower limb L3-40

ICD-10 mortalityNature of injuryCategories

FracturesDislocationInternal organ injuriesOpen woundsAmputationsBlood vesselsSuperficial & contusionCrushingBurnsEffects of foreign bodyOther effects of external

causesPoisoningToxic effectsMultiple injuriesOther specifiedSprain or strainMuscle and tendon injuriesNerve injuriesUnspecified

Level 1

Level 2

Total and any mentions of injury Total and any mentions of injury diagnoses by body region: 2002diagnoses by body region: 2002

0

10,000

20,000

30,000

40,000

50,000

60,000

70,000

80,000

# of mentions

Total mentionsAny mention

Total and any mentions of injury Total and any mentions of injury diagnoses by nature of injury: diagnoses by nature of injury:

20022002

-

10,000

20,000

30,000

40,000

50,000

60,000

70,000

80,000

# of mentions

Total mentions

Any mention

Injuries mentioned in MVT deaths Injuries mentioned in MVT deaths (44,065 deaths and 70,684 injuries) by body (44,065 deaths and 70,684 injuries) by body

region and nature of injury: US, 2002region and nature of injury: US, 2002

- 10.0 20.0 30.0 40.0

Head & Neck

Spine & Back

Torso

Extremities

Not classifiable byregion

Percent of all injuries mentioned

Fracture

Internal

BloodvesselMultiple

Other

Unspecified

Under discussion..Under discussion..How should we define How should we define

poisoning?poisoning?

• ICD-9 vs ICD-10

• Underlying cause: external cause codes (ICD-10 X & Y codes)

• ICD-10 Multiple cause: T codes for substances

• Mental health “F” codes

• Nondependent abuse

• Dependent abuse

• Alcohol intoxication (not included here)

• Adverse effects codes (not included here)

Definitional issues: poisoning Definitional issues: poisoning mortalitymortality

ICD ‘definitions’ of drug ICD ‘definitions’ of drug poisoningpoisoning

ICD-10

Nondependent abuse of drugs 305.2-.9 F11-16, 18-19 (not .2)

Dependent abuse 304 F11-16,18-19(.2)

Unintentional E850-E858 X40-X44

Suicide E950(.0-5) X60-X64

Undetermined E980(.0-.5) Y10-Y14

Homicide E962.0 X85

[Alcohol intoxication 305.0 F10.0]

ICD-9

ICD-9 vs ICD-10ICD-9 vs ICD-10Substance selectionSubstance selection

• ICD-9 underlying cause codes for poisoning more specific than ICD-10 codes

• ICD-10, to get specific substances

• Literals from the death certificate

•Code the multiple cause data

ICD mortality coding varies by ICD mortality coding varies by countrycountry

ICD-9-UCOD

ICD-10-UCOD

Substance-specific

England and Wales

1990-2000

2001-2002 Literals from text files

Canada 1990-1999

2000-2002 From under-lying cause

United States

1990- 1998

1999-2002 Multiple cause coding

Drug poisoning death rates: US, Drug poisoning death rates: US, 20022002

0.0

2.0

4.0

6.0

8.0

10.0

12.0

14.0

Under15

15-24 25-34 35-44 45-54 55-64 65-74 75-84 85+

Unintentional

Suicide

Undetermined

DAD

NDAD

Deaths per 100,0000 pop

Leading specified substances Leading specified substances mentioned in drug deaths for 35-54 mentioned in drug deaths for 35-54

year olds: US, 2002year olds: US, 2002

1. Cocaine T40.5: 25%

2. Other specified opioids T40.2: 21%

3. Antidepressants T43.0-T43.2: 11%

4. Alcohol T51: 11%

5. Carbon Monoxide T58: 8%

6. Heroin T40.1: 10%

7. Benzodiazepines T42.4: 9%

8. Methadone T40.3 10%

Next StepsNext Steps

• In 2003, the MRG recommended to the URC of the WHO that new rules will apply in January 2006 to the underlying cause coding of certain ICD codes from Mental and Behavioral Disorders (F10-F19)

• If there is any mention of an external cause on the certificate, the code will be to the external cause rather than MBD code

• Codes in the F10-F19 range with a 4th digit of .0 (acute intoxication) will be coded to poisoning codes in the external cause of poisoning section

Injury SeverityInjury Severity

Some new considerations for national data

Acknowledging many of these next slides from

Dr. Ellen MacKenzie, Johns Hopkins University

September 2004 MeetingSeptember 2004 Meeting

• Meeting convened at NCHS bringing together national and international experts in the area of injury severity scoring

• Why? Because the current standards “AIS” and “ICDMAP” are proprietary and many believe that

•There are nonproprietary alternatives

•They should not be proprietary any longer

INJURY SEVERITYINJURY SEVERITY

Alphabet SoupAlphabet Soup

EM

Injury Severity Indices:Injury Severity Indices:Major Areas of ApplicationMajor Areas of Application

Triage

Prognostic Evaluation

Research and Evaluation Clinical Research

Systems Evaluation

Surveillance and Epidemiology

EM

The Abbreviated Injury Scale The Abbreviated Injury Scale (AIS)(AIS)

A classification of injuries based on anatomic descriptors

A severity score ranging from 1 (minor) to 6 (maximum injury, virtually unservivavle) assigned to each injury

EM

Scores are subjective Scores are subjective assessments assigned by a assessments assigned by a group of experts and implicitly group of experts and implicitly based on based on fourfour criteria: criteria:

Threat to life

Permanent Impairment

Treatment Period

Energy Dissipation

EM

AISAIS

Currently, most widely used severity score based on anatomic descriptors

Official injury data collection tool of NHTSA crash investigation teams

Developed in 1971; 5th revision to be published in 2005

EM

Using AIS for Multiple InjuriesUsing AIS for Multiple Injuries

for predicting survivalfor predicting survival

Injury Severity Score (ISS)

The New Injury Severity Score (NISS)

The Anatomic Profile (AP) and the Anatomic Profile Scale (APS)

EM

ICD-Based Measures ICD-Based Measures

of Injury Severityof Injury Severity

ICD to AIS Conversion

ICISS Family of Measures

EM

ICDMAPICDMAPICD-CM to AIS ConversionICD-CM to AIS Conversion

Converts ICD-9CM coded discharge diagnoses into AIS injury descriptors, AIS scores and computes ISS, NISS, APS

Conservative measure of injury severity - refer to as ICD/AIS scores

Limitations identified; revision needed

EM

ICISSICISS

Based strictly on ICD rubrics

The ICISS score for a given patient is the product of the survival risk ratios (SRRs) associated with each ICD diagnosis

SRRs are calculated by dividing the number of survivors among patients with a specific ICD by the total number of patients with that ICD code

EM

Refining the ICISSRefining the ICISS

Computation of SRRs: based on multiple trauma patients or patients with single injuries?

Database used for calculation of SRRs:

Trauma centers only vs. population based ?

Include ALL deaths, only deaths in ED or hospital or only in-hospital deaths ?

Registry data vs. administrative data ?

Regional/local vs. national data?

Computation of ICISS: use product of SRRs or lowest SRR?

EM

To think about….To think about….

Need to keep in mind the application; severity (case mix?) adjustment for use with hospital discharge data (HDD) – also mortality data, ambulatory care encounter data ?

By necessity – must be based on ICD (but what do we lose – how good can we get without physiology ?)

Age, gender, co-morbidities and mechanism are important in case mix adjustment – and all are measurable using HDD

EM

and . . .and . . .

Are we just interested in measures that predict mortality ?

Need to carefully consider the overall advantages (current and future) of the AIS classification in any recommendations

What are implications of the 2005 revision of the AIS and the ICD-10 (CM??)

EM

What we knowWhat we know

• National trends in injury-related hospital discharges and emergency dept. visits reflects utilization, but not differences in injury severity

• ICD codes alone cannot distinguish severity among injuries

• ICD-10 has provided no real guidance on how to select a main injury among multiple cause of injury mortality data

The “practical problems”The “practical problems”

• ICD-9 CM is still being used for coding morbidity data; annual updates to CM continue

• Most recent version of ICDMAP doesn’t recognize new codes

• ICD-10 CM doesn’t yet have an implementation date and there is no new ICDMAP based on ICD-10

• ICD codes used for mortality data often lack specificity

What was discussedWhat was discussed

• Strengths and weaknesses of different severity scales

• Solutions for administrative data acknowledging the limitations of the source data (e.g., non-specific coding, changes in admission practices)

• Can we measure threat to function as well as threat to life?

What “we” would have liked What “we” would have liked to accomplishto accomplish

• Agree upon a measure of injury severity to add to NCHS survey data

• Incorporate a method to identify the “main injury” in mortality and add it to the mortality file

• Recommend a standard measure to users of administrative databases (e.g., Statewide hospital discharge data sets)

Where might these measures be Where might these measures be used?used?

• Tracking Department’s Healthy People Objectives

• CDC Futures Initiative- Health Protection Goals

• NCHS reports: Health, United States

• Injury Chart book(s)

• Statewide trauma and general injury databases

NCHS Data Sources for NCHS Data Sources for Injury SeverityInjury Severity

• National Hospital Discharge Survey

• National Hospital Ambulatory Medical Care Survey-ED component

• National Health Interview Survey ??

• Mortality data from vital statistics

Other Federal SourcesOther Federal Sources

• Agency for Health Care Research and Quality

•Medical Expenditure Panel Survey (MEPS)

•Healthcare Cost & Utilization Project (HCUP)•Nationwide Inpatient Sample (NIS)•State inpatient databases (SID)•State emergency dept databases (SEDD)

http://www.ahrq.gov/data/hcup/

Discharge Disposition for Discharge Disposition for injury diagnoses: NHDS, injury diagnoses: NHDS,

20022002

62%

26%

9%

2%

1%

Routine/home

Transferred

NS (but known alive)

Died

Not stated

Survival Risk Ratios (SRR’s): Survival Risk Ratios (SRR’s): NHDS, 2002NHDS, 2002

0.860

0.880

0.900

0.920

0.940

0.960

0.980

1.000

Based on all 7 dx fields;Ordered by # of discharges

Discharged alive: all discharges

11stst listed injury dx by nature of listed injury dx by nature of injury grouped by AIS: NHDS, injury grouped by AIS: NHDS,

1999-20021999-2002

0%

10%

20%

30%

40%

50%

60%

70%

80%

90%

100%

All Fractures Spr/str Int org Openwounds

Super/cont Burns Unspec

AIS 1-3

AIS 4

AIS 5-6

AIS 9

% of 1st listed dx AIS 1-9

NHAMCS- ED: Percent hospitalized NHAMCS- ED: Percent hospitalized by nature and body region of by nature and body region of

injury, injury, 1999-20021999-2002

0.0

5.0

10.0

15.0

20.0

25.0

% of all injury visits

NHIS: “severity” variables in NHIS: “severity” variables in addition to nature of injuryaddition to nature of injury

• Days out of school

• Days out of work

• Hospitalized

• Any limitations of activity

Mortality data from NVSSMortality data from NVSS• ICD-10: uses all digits; up to 20 listed

diagnoses

• For 2001, range (0-15 injuries listed)

• 1 injury listed 65% of deaths

• 2 injuries 22%

• 3 injuries 8%

• 4 -15 injuries 4%

• How can we select the most severe injury?

• Do we need to include underlying cause of death?

So…So…

• Most hospitalized injuries are not fatal

• Most ED visits don’t result in hospitalization

• Too many mortality records lack detailed diagnosis codes

Optimism….Optimism….

• SRR’s and ICISS can be readily calculated from hospital discharge data – we are creating a file with them that will be on the web

• AIS could theoretically be added also to hospital discharge data file once it is in public domain and ICDMAP is updated

• Main injury (method yet to be determined) will be added to mortality file

Consensus (well almost….)Consensus (well almost….)

• AIS and ICDMAP should be maintained and updated

• BOTH should be non-proprietary

• ICISS is a useful alternative to the current non-updated ICDMAP

•Statistical methods need continued evaluation and improvement•Lowest SRR may be better than

ICISS

Visit us at:Visit us at: www.cdc.gov/nchs/injury.htmwww.cdc.gov/nchs/injury.htm

Email us at: nchsinjury@cdc.govEmail us at: nchsinjury@cdc.gov