Average medical cost of fatal and non-fatal injuries by type in the USA

Abstract

Objective
To estimate the average medical care cost of fatal and non-fatal injuries in the USA comprehensively by injury type.

Methods
The attributable cost of injuries was estimated by mechanism (eg, fall), intent (eg, unintentional), body region (eg, head and neck) and nature of injury (eg, fracture) among patients injured from 1 October 2014 to 30 September 2015. The cost of fatal injuries was the multivariable regression-adjusted average among patients who died in hospital emergency departments (EDs) or inpatient settings as reported in the Healthcare Cost and Utilization Project Nationwide Emergency Department Sample and National Inpatient Sample, controlling for demographic (eg, age), clinical (eg, comorbidities) and health insurance (eg, Medicaid) factors. The 1-year attributable cost of non-fatal injuries was assessed among patients with ED-treated injuries using MarketScan medical claims data. Multivariable regression models compared total medical payments (inpatient, outpatient, drugs) among non-fatal injury patients versus matched controls during the year following injury patients’ ED visit, controlling for demographic, clinical and insurance factors. All costs are 2015 US dollars.

Results
The average medical cost of all fatal injuries was approximately $6880 and $41 570 per ED-based and hospital-based patient, respectively (range by injury type: $4764–$10 289 and $31 912–$95 295). The average attributable 1-year cost of all non-fatal injuries per person initially treated in an ED was approximately $6620 (range by injury type: $1698–$80 172).

Conclusions and relevance
Injuries are costly and preventable. Accurate estimates of attributable medical care costs are important to monitor the economic burden of injuries and help to prioritise cost-effective public health prevention activities.

Full text

Average medical cost of fatal and non-fatal injuries by type in
the USA
Cora Peterson1, Likang Xu2, Curtis Florence2
1National Center for Injury Prevention and Control, Centers for Disease Control and Prevention,
Atlanta, Georgia, USA.
2National Center for Injury Prevention and Control, Centers for Disease Control and Prevention,
Atlanta, Georgia, USA.
Abstract
Objective—To estimate the average medical care cost of fatal and non-fatal injuries in the USA
comprehensively by injury type.
Methods—The attributable cost of injuries was estimated by mechanism (eg, fall), intent (eg,
unintentional), body region (eg, head and neck) and nature of injury (eg, fracture) among patients
injured from 1 October 2014 to 30 September 2015. The cost of fatal injuries was the
multivariable regression-adjusted average among patients who died in hospital emergency
departments (EDs) or inpatient settings as reported in the Healthcare Cost and Utilization Project
Nationwide Emergency Department Sample and National Inpatient Sample, controlling for
demographic (eg, age), clinical (eg, comorbidities) and health insurance (eg, Medicaid) factors.
The 1-year attributable cost of non-fatal injuries was assessed among patients with ED-treated
injuries using MarketScan medical claims data. Multivariable regression models compared total
medical payments (inpatient, outpatient, drugs) among non-fatal injury patients versus matched
controls during the year following injury patients’ ED visit, controlling for demographic, clinical
and insurance factors. All costs are 2015 US dollars.
Results—The average medical cost of all fatal injuries was approximately $6880 and $41 570
per ED-based and hospital-based patient, respectively (range by injury type: $4764–$10 289 and
$31 912–$95 295). The average attributable 1-year cost of all non-fatal injuries per person initially
treated in an ED was approximately $6620 (range by injury type: $1698–$80 172).
Conclusions and relevance—Injuries are costly and preventable. Accurate estimates of
attributable medical care costs are important to monitor the economic burden of injuries and help
to prioritise cost-effective public health prevention activities.
Correspondence to Dr Cora Peterson, National Center for Injury Prevention and Control, Centers for Disease Control and Prevention,
Atlanta, Georgia, USA; cora.peterson@cdc.hhs.gov.
Contributors CP led the study design and interpretation of results and drafted the manuscript. LX and CP conducted data analysis.
LX and CF assisted with the study design and interpretation of results. All authors edited the manuscript and approved the final
manuscript as submitted.
Patient consent for publication Not required.
Provenance and peer review Not commissioned; externally peer reviewed.
Data availability statement Data sources are publicly available through third parties.
Competing interests None declared.
HHS Public Access
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INTRODUCTION
Injuries are a leading cause of mortality and morbidity in the USA. In clinical and public
health terms, injuries comprise a range of unintentional and violence-related outcomes, for
example, MVCs, drug poisoning, falls, suicide and assaults. Unintentional injuries are the
third leading cause of death, and along with suicide contributed to decreases in overall life
expectancy during 2016 and 2017.1 There are 30 million emergency department (ED) visits
for non-fatal injuries each year,2 and US medical expenditures for injury and poisoning
exceed $133 billion annually.3
Medical care cost estimates are important to monitor the economic burden of injuries and
help to prioritise cost-effective public health prevention activities. Existing comprehensive
estimates of medical care cost for injuries by injury type—mechanism (eg, fall), intention
(eg, unintentional), body region (eg, head and neck) and nature of injury (eg, fracture)—
were calculated using primarily hospital-based data from 2010,4 and have been applied in
numerous assessments of the economic and public health impact of violence and
unintentional injuries.5-10 The aim of this study was to estimate the average medical care
cost of fatal and non-fatal injuries in the USA comprehensively by injury type.
METHODS
Medical cost estimates from the perspective of the healthcare payer for fatal and non-fatal
injuries treated from 1 October 2014 to 30 September 2015 were derived from two publicly
available data sources—Healthcare Cost and Utilization Project (HCUP) (www.hcup-
us.ahrq.gov) hospital discharge databases (figure 1) and MarketScan (www.ibm.com)
medical claims databases (figure 2). The time horizon for fatal costs was the ED visit or
hospitalisation which ended in death, and the time horizon for non-fatal costs was 1 year.
Medical costs were estimated by injury mechanism and intent11 (table 1 for fatal and table 2
for non-fatal) and body region and nature of injury12 (table 3 for fatal and table 4 for non-
fatal) using established classifications based on the International Classification of Diseases,
Ninth Revision, Clinical Modification (ICD-9-CM) diagnosis codes11 and External Cause of
Injury codes (E-codes). Both types of injury classification—mechanism/intent and body
region/nature of injury—are important in different contexts, and costs per injury type are not
comparable across classifications. For example, patients with different injury types by body
region (eg, torso vs head) can have the same injury type by mechanism (eg, motor vehicle
traffic) or vice versa. Transition to ICD-10-CM coding for medical payments occurred
outside the study period, on 1 October 2015.12 ICD-10-CM injury classification frameworks
are proposed and will be finalised in the future (www.cdc.gov/nchs/injury). Costs are
presented in 2015 US dollars (not inflated from 2014 to 2015 data source values).
Fatal injuries
Data—The medical cost of fatal injuries was assessed among patients with a primary
diagnosis of injury11 who died in a hospital ED or inpatient setting as reported in the HCUP
Nationwide Emergency Department Sample (HCUP-NEDS) and National Inpatient Sample
(HCUP-NIS) (figure 1). These data sources can produce nationally representative estimates
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of ED visits and inpatient admissions to community hospitals. HCUP-NEDS and HCUP-
NIS demonstrate hospital facility charges per ED visit or admission, edited to exclude
extreme dollar values.
Hospital charges are distinct from payments hospitals receive from individuals or health
insurance companies and typically do not include physician (or professional) fees,
ambulance fees, nor coroner/medical examiner (C/ME) fees—each separately estimated for
this study. The estimated medical cost per fatal injury in an ED or inpatient hospital was
calculated as the facility charge value from HCUP-NEDS or HCUP-NIS multiplied by an
HCUP hospital-specific cost-to-charge ratio (CCR) and a diagnosis-specific professional fee
ratio (PFR), plus estimated ambulance and C/ME costs—each element as detailed below.
Annual, all-payer, hospital-specific, inpatient CCRs are calculated by the US Centers for
Medicare and Medicaid Services and published for use with HCUP-NIS (www.hcup-
us.ahrq.gov). When hospital-specific CCR was unavailable (approximately 2% of HCUP-
NIS analysed injury records; data not shown), the authors used multiple imputation to
estimate CCR based on selected hospital characteristics (regional and urban/rural location,
teaching status and bed size).13 This yielded an average inpatient CCR of 0.337 (data not
shown), suggesting hospitals’ facility cost was approximately 34% of the facility charge
value among analysed records. HCUP does not publish CCR for NEDS data.14 The authors
estimated CCR for HCUP-NEDS records by applying the average inpatient CCR among
analysed HCUP-NIS records based on the aforementioned hospital characteristics; for
example, an injury ED visit at an urban teaching hospital in the Midwest was assigned the
average inpatient CCR for all hospitals in the HCUP-NIS analysis sample with those criteria.
13 The average CCR applied to HCUP-NEDS records was 0.396 (data not shown). PFR was
assigned to injury records by primary three-digit ICD-9-CM code and primary payer
(Medicare and Medicaid were assigned Medicaid-specific PFR, and private insurance, self-
pay, no charge, other and missing payers were assigned commercial insurance-specific PFR)
separately for ED visits and admissions using published estimates (from 2012, the most
recent available).15 If PFR was not available for a given ICD-9-CM code, the authors
applied the all-diagnosis, payer-specific adjusted average PFR.15
Each fatal injury in an ED or inpatient setting was also assigned an estimated average cost of
ambulance transport and C/ME (including autopsy) costs. An average ambulance cost of $70
was based on national survey data (2015 National Hospital Ambulatory Medical Care
Survey, the most recent available) indicating 15.1% of ED visits (all diagnoses) have
ambulance transport16 at a nationwide estimated cost of $463 per ambulance transport
(inflated17 from the reported 2010 US dollar cost of $429).18 Majority of US states require
death investigation for deaths due to injury/casualty, suicide or violence.19 An average C/ME
cost estimate of $929 (inflated20 from the reported 2004 US dollar cost of $752) was based
on a nationwide survey of C/ME offices indicating a combined annual budget of $718.5
million in 2004, when such offices were referred 956 000 deaths.21
Analysis—The authors used SAS V.9.4 to derive patient samples and Stata V.14 for
regression models. The adjusted average cost per fatal injury in an ED or inpatient setting
was estimated using generalised linear models (GLM) (Stata V.14
svy glm family(gamma)
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link(log)
) with postestimation calculation of the average of model-predicted values (in dollar
units, using Stata V.14
margins
) per injury type (ie, by mechanism, intent, body region and
nature of injury). With total ED or admission (including any preceding ED) estimated
medical cost as the dependent variable, the regression models controlled for patients’ sex
(male, female), age (years), race/ethnicity (hospitalisations only; white, black, Hispanic,
Asian or Pacific Islander, Native American, other, unknown), number of comorbidities (0, 1,
2+) diagnosed on the visit or admission record (based on Elixhauser Comorbidity Software
V.3.7; www.hcup-us.ahrq.gov) and primary payer (Medicare, Medicaid, private insurance,
self-pay, other (e.g., worker’s compensation, other government programmes), no charge,
unknown). Injury type elements were included as covariates as relevant (eg, the model of
costs among all patients with fatal cut/pierce (mechanism) injuries controlled for injury
intent—unintentional, self-inflicted, assault, undetermined, other or unknown). Based on
standard US death certificate reporting on place of death, adjusted average costs per injury
type are reported here in terms of whether a patient died in an ED or inpatient setting (table
1 for mechanism and intent and table 2 for body region and nature of injury). The number of
analysed records, estimated simple mean cost and 95% CI for simple and regression-
adjusted mean costs per injury type are reported in online supplementary tables S1-S4.
Non-fatal injuries
Data—The estimated attributable 1-year medical cost of non-fatal injuries was assessed
among patients with ED-treated injuries as reported in the MarketScan Outpatient Services
(primarily treat-and-release) and Inpatient Services (hospitalisation following ED treatment)
databases. MarketScan includes hundreds of millions of covered lives based on data from
large employers, health plans, and government and public organisations, including some
state Medicaid payers, and is not nationally representative. Patients with commercial health
insurance (including Medicare supplemental plans for enrollees >64 years old) and Medicaid
were analysed based on their first chronological ED visit during the study period with a
primary visit diagnosis of injury--or, index injury ED visit (figure 2). Because these
databases can have more than one primary diagnosis listed per patient per ED visit, the
primary visit diagnosis was defined as the primary diagnosis on the ED claim record to
which facility charges for the visit were assigned. Patients admitted following the index
injury ED visit were identified by an admission record (ie, MarketScan Inpatient Admissions
database) on the date of or day following the index injury ED visit. The total 1-year medical
payments were the sum of medical claims (reported in Market-Scan Outpatient Services,
Inpatient Admissions—an aggregated version of Inpatient Services data—and Outpatient
Pharmaceutical Claims databases) during the 365 days following (and including) each injury
patient’s index injury ED visit date (ie, varying observation dates during 2014–2016 per
patient with injury). Negative dollar value payments can exist in medical claims data (eg,
adjustments). The authors excluded injury patients with ≤$0 total payments for the total 1-
year observation period, as well as patients with capitated insurance payment plans (fee-for-
service payments are presumed to reflect the cost of care associated with particular
diagnoses in medical claims databases, while payments for patients with capitated plans
likely do not).
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To estimate the combined cost of acute and follow-up medical care attributable to non-fatal
injuries, the total 1-year medical payments of patients with injury were compared with total
1-year payments among control enrollees with no injuries during the observation period.
Patients with injury were matched to controls (SAS V.9.4
gmatch
) 1:5 using MarketScan
Enrollment Detail tables (match methods in figure 2 notes). Health insurance enrollees with
$0 medical payments can exist in medical claims data—for example, no medical visits
during a given observation period—and enrollees observed for a specific period can have
negative total payment values (eg, adjustments for services prior to the observation period).
The total 1-year medical payments for control enrollees were set to a minimum of $0.
Among combined patients with injury and controls, the 99th percentile for the total 1-year
medical payments was $117 414 and the highest value was $4.8 million; therefore, the top
one percentile was top-coded to the 99th percentile value for analysis.22Top-coding is a
common approach when medical payments—sometimes highly skewed due to a small
number of patients with very high costs—are dependent variables in a regression model.22
Analysis—The 1-year attributable cost of non-fatal injuries was estimated using individual
two-part models (Stata V.14
twopm firstpart(logit) secondpart (glm, family (gamma)
link(log)) vce (robust)
) per injury type (mechanism, intent, body region and nature of
injury), with injury patients’ and matched controls’ total 1-year medical payments starting
from the injury patient’s index injury ED visit date as the dependent variable. A two-part
model accommodated control enrollees with $0 medical payments during the observation
period—in the first part, a logistic regression model predicts the probability of >$0 medical
payments, and in the second part a GLM model assesses costs among patients with >$0
payments. The regression models controlled for all matching factors (eg, patient age, sex and
so on) as covariates in both the logistic and GLM parts. Because all patients with injury had
>$0 total 1-year medical payments, the two-part model can accommodate an injury covariate
(ie, identifying patients with injury) in the GLM, but not logistic, part of the modelling
approach. The regression-adjusted marginal cost of non-fatal injuries by type was estimated
as the marginal effect of the injury covariate (in dollar units, using postestimation Stata V.14
margins, dydx (injury
)) among all observations (patients with injury and controls).
Results are reported by injury type (table 3 for mechanism and intent and table 4 for body
region and nature of injury). The number of analysed patients with injury and controls,
simple mean and 95% CIs for total 1-year medical payments, and modelled injury cost are
reported in online supplementary tables S5 and S6. The online supplementary file also
demonstrates results for two mutually exclusive subgroups of patients with injury: patients
treated and released (T&R) from the index injury ED visit and patients admitted after the
index injury ED visit (patient counts in figure 2) (online supplementary tables S7-S10).
Group characteristics of patients with injury versus matched controls (eg, average age) are
also reported (online supplementary table S11).
RESULTS
The estimated average attributable medical cost of fatal injuries (all types combined) in ED
and inpatient settings was approximately $6880 and $41 570, respectively—these are
median values between the modestly different cost results observed among the same patients
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(n=9929 and n=40 650 survey-weighted) depending on whether costs per injury type were
modelled by mechanism and intent (table 1; $6884 and $41 605) or body region and nature
of injury (table 2; $6885 and $41 541). The cost per injury fatality in an ED ranged from
$4764 (95% CI 3913 to 5615; system-wide injuries) to $10 289 (95% CI 8210 to 12 368;
blood vessel injuries), and the range per injury fatality in inpatient settings was $31 912
(95% CI 29 123 to 34 702; unspecified head and neck injuries) to $95 295 (95% CI 74 733
to 115 857; other or multiple injuries) (tables 1 and 2 for point estimates; online
supplementary tables S1-S4 for 95% CIs).
The estimated average 1-year attributable medical cost of non-fatal injuries (all types
combined) initially treated in an ED was approximately $6620—again, this is the median for
this measure among the same patients (n=818 053 injury, n=3 975 125 control) depending
on whether costs per injury type were modelled by mechanism and intent (table 3; $6658) or
body region and nature of injury (table 4; $6587). The cost per non-fatal injury type ranged
from $1698 (95% CI 421 to 2974; other specified, classifiable injuries of undetermined
intent) to $80 172 (95% CI 46 917 to 113 427; spinal cord fractures) (tables 3 and 4 for point
estimates; online supplementary tables S5-S6 for 95% CIs). The comparable costs among
ED T&R versus ED then admitted patients were approximately $5580 and $49 670,
respectively (online supplementary tables S7-S10). Comparable ranges by injury type
among ED T&R patients were $1484 (95% CI 281 to 2687; other specified, classifiable
injuries of undetermined intent) to $40 373 (95% CI 24 874 to 55 873; lower extremity
amputations) and from $15 607 (95% CI 7805 to 23 409; upper extremity dislocation) to
$107 400 (95% CI 49 706 to 165 094; firearm assault) among admitted patients (online
supplementary tables S7-S10).
DISCUSSION
This study generated updated medical care cost estimates for US fatal and non-fatal injuries
comprehensively by injury type. Where sample size permitted, costs were estimated for each
type in two common injury classifications—mechanism/intent and body region/nature of
injury. This breadth and specificity of estimated costs were made possible through large,
nationally representative (HCUP) or multistate (MarketScan) databases containing
information on tens to hundreds of thousands (survey-weighted) of patients with injury, as
well as computing power to facilitate hundreds of consecutive regression models using
different patient samples to estimate attributable average costs. Where previous estimates of
medical costs by injury type4 relied primarily on 1 year of hospital-based data, this study
observed medical care payments for all clinical settings for 1 year among patients with non-
fatal ED-treated injuries, and compared such payments with non-injury insurance enrollees
to estimate the total 1-year attributable cost of injuries.
The range of injury types depicted in the two injury classification schemes and the range of
outcomes (fatal and non-fatal) assessed here created a broad range of estimated average
medical cost values by injury type—from approximately $1700 (non-fatal, ED-treated other
specified, classifiable, injuries of undetermined intent; table 2) to approximately $95 300
(fatal, inpatient-treated other or multiple/unclassifiable by site injuries; table 3). For context,
in 2016 the estimated simple average costs of an ED visit and hospital admission (all
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diagnoses, all dispositions) were $1917 and $20 929, respectively, reflecting the nationally
representative cost among patients aged <65 years with employer-sponsored health
insurance.23 The higher estimated costs in this study for some injury ED visits and
admissions are likely due to injury severity among visits and admissions ending in death, the
longer duration and scope of assessed services and costs for non-fatal injuries, this study’s
inclusion of older (>64 years) patients, and presumably the higher prevalence of surgical
services among patients with injury (the 2016 average cost of surgery admission from the
aforementioned comparative source was more than double the cost of medical admission23).
In presenting estimated costs for the two injury classification schemes in their entirety
(tables 1-4), this study’s results highlight that many injury types are uncommon, and
therefore medical costs for such types may be best approximated through aggregated
categories, for example, combined intent categories for a given mechanism. In such
instances, this analysis has provided regression-adjusted estimates for aggregated injury
categories (eg, cut/pierce, all intent; Tables 1 and 2), controlling for injury attributes (eg,
intent) when sample sizes even in the large databases assessed for this analysis did not
permit stratification by detailed injury type.
Limitations
This study did not investigate factors associated with higher injury costs among patients with
the same injury type and did not present estimates by geography within the USA. There is
some evidence that inpatient CCR may underestimate ED CCR.14 Patients with non-fatal
injury were classified by their first chronological injury during the observation period;
subsequent injuries during were not classified. This analysis assessed fatal injury medical
costs using hospital discharge data, which do not capture non-hospital medical costs among
patients who die in nursing homes or non-hospital hospice settings following hospital
treatment. Previous injury cost estimates assumed nursing home and hospice location injury
deaths each incurred the cost of hospital admission plus an average cost of nursing home
care; for example, the nursing home semiprivate room median cost per day ($220 in 2015
US dollars24) multiplied by the median duration of nursing home care before death (5
months25; all diagnoses, not separately available for injury diagnoses), or $33 458 per
patient for nursing home location deaths and $11 5062627 per hospice location death.4 Non-
fatal injury costs were assessed over the subsequent 1 year following an index injury ED
visit, which underestimates medical costs for injuries resulting in long-term physical
disability—for example, traumatic brain injuries and spinal cord injuries—as well as injuries
such as violent assault that result in long-term mental health consequences.91028
CONCLUSION
Fatal and non-fatal injuries in the USA are preventable and incur substantial medical costs.
Accurate information on the medical cost of injuries is important to monitor the economic
burden of injuries and help to prioritise cost-effective public health prevention activities.
Supplementary Material
Refer to Web version on PubMed Central for supplementary material.
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Acknowledgments
Funding The authors have not declared a specific grant for this research from any funding agency in the public,
commercial or not-for-profit sectors.
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What is already known on the subject
•Injuries are formally classified into hundreds of types—by mechanism (eg,
fall), intent (eg, unintentional), body region (eg, head and neck) and nature of
injury (eg, fracture).
•Accurate estimates of attributable medical care costs are important to monitor
the economic burden of injuries and help to prioritise cost-effective public
health prevention activities.
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What this study adds
•This study estimated average medical care costs due to fatal and non-fatal
injuries in the USA comprehensively by injury type.
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Figure 1.
Sample selection of emergency department visits and admissions for fatal injuries in the
Healthcare Cost and Utilization Project National Inpatient Sample and Nationwide
Emergency Department Sample, from 1 October 2014 to 30 September 2015. aSurvey-
weighted number of admissions or ED visits. bInjury diagnosis for the emergency
department visit (HCUP-NEDS) or inpatient admission (HCUP-NIS) defined by an injury
code (ICD-9-CM) in the primary diagnosis field. Complete data for analysis included
admission or ED visit charges, sex (male, female), age, race/ethnicity (white, black,
Hispanic, Asian or Pacific Islander, Native American, other, unknown; HCUP-NIS records
only, not reported in HCUP-NEDS), and primary payer for admission or ED visit (Medicare,
Medicaid, private insurance, self-pay, other (e.g., worker’s compensation, other government
programmes), no charge, unknown). Data sets were reweighted following exclusion of
records with missing data (eg, charges) to maintain data set representativeness. HCUP-
NEDS, Healthcare Cost and Utilization Project Nationwide Emergency Department Sample;
HCUP-NIS, Healthcare Cost and Utilization Project National Inpatient Sample; ICD-9-CM,
International Classification of Diseases, Ninth Revision, Clinical Modification.
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Figure 2.
Sample selection of patients with non-fatal ED-treated injuries in MarketScan, from 1
October 2014 to 30 September 2015. aDefined as ICD-9-CM injury diagnosis in the primary
diagnosis field from 1 October 2014 to 30 September 2015 during ED visit (variable:
SVCSCAT=xxx20) plus facility payment (variable: FACPROF) attributed to the injury
diagnosis as identified in MarketScan Outpatient Services (ie, primarily treat-and-release
patients) and Inpatient Services (ie, patients with hospitalisation following ED visits)
databases (https://www.ibm.com/us-en/marketplace/marketscanresearch-databases).
bComplete data for analysis included medical cost in the 12 months following ED injury
visit (including index injury date) >$0 (patients with injury only), sex (male, female), age
(years), race/ethnicity (white, black, Hispanic, Asian or Pacific Islander, Native American,
other, unknown; Medicaid enrollees only), region of residence (based on metropolitan
statistical area; records with ‘unknown’ but not missing value included; commercial
insurance and Medicare supplemental enrollees only), type of health plan (eg, health
management organisation) and basis for Medicaid eligibility (eg, foster care; Medicaid
enrollees only). cTo ensure controls had the appropriate observation timeline—24 months
surrounding injury patients’ index visit month—all potential control enrollees (non-injury)
in the 2015 MarketScan Enrolment Detail table were first randomly assigned an index month
(ie, values 1–12) and excluded if lacking 24 months of insurance enrolment surrounding that
index month. Next, 1:5 injury patient to control enrollee match (SAS V.9.4
gmatch
) was
requested based on index month (ie, month of index injury ED visit for patients with injury
and randomly assigned monthly for control enrollees), insurance type (commercial,
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Medicare or Medicaid), enrollee age (as reported in the data source for commercial
insurance and Medicare supplemental patients, and for Medicaid enrollees based on reported
year of birth), sex (male/female), race/ethnicity (reported in the data source for Medicaid
enrollees only), region of residence (reported in the data source for commercial insurance
and Medicare supplemental enrollees only), type of health plan, mental health and substance
abuse treatment coverage (commercial insurance enrollees only), drug coverage, Medicare
dual eligibility (Medicaid enrollees only), comorbidity count (0, 1, 2+ diagnosed in the 12
months prior to the index injury date (based on Elixhauser Comorbidity Software V.3.7) in
any clinical location reported in MarketScan), and basis for Medicaid eligibility (Medicaid
enrollees only). ED, emergency department; Hosp, hospitalised (inpatient); ICD-9-CM,
International Classification of Diseases, Ninth Revision, Clinical Modification; T&R, treated
and released.
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Table 1
Adjusted mean cost of ED visits and admissions for fatal injuries by mechanism and intent (total n=40 650 survey-weighted)
Mechanism Fatality location Unintentional Self-inflicted Assault undetermined Other Unknown All intents
Cut/pierce ED $6782 $7115
Hospital $44 244 $51 946 $52 110
Drowning/submersion ED $6351 $6462
Hospital $55 968 $59 294
Fall ED $7207 $7317
Hospital $36 568 $36 440
Fire/burn ED
Hospital $41 682 $41 985
Fire/flame ED
Hospital $42 203 $42 452
Hot object/substance ED
Hospital $38 399 $38 735
Firearm ED $6660 $6966 $6682 $6726 $6644
Hospital $51 197 $42 179 $50 636 $44 845 $44 887
Machinery ED
Hospital
Motor vehicle traffic ED $6989 $7160
Hospital $46 063 $48 157
Occupant ED $7138 $7316
Hospital $45 841 $47 934
Motorcyclist ED $6793 $6957
Hospital $47 249 $49 549
Pedal cyclist ED
Hospital $49 305 $51 420
Pedestrian ED $6947 $7117
Hospital $45 195 $46 901
Unspecified motor vehicle ED $6650 $6824
Hospital $47 129 $49 861
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Mechanism Fatality location Unintentional Self-inflicted Assault undetermined Other Unknown All intents
Other pedal cyclist ED
Hospital $46 237 $47 073
Other pedestrian ED
Hospital $40 626 $41 629
Other transport ED $7007 $7224
Hospital $45 024 $46 663
Natural/environmental ED $6903 $6987
Hospital $47 517 $48 894
Bites and stings ED
Hospital
Overexertion ED
Hospital
Poisoning ED $7163 $7113 $7199 $6507
Hospital $50 853 $48 210 $51 490 $40 646
Struck by/against ED $7220
Hospital $42 392 $52 043 $50 987
Suffocation ED $6662 $6590 $6155
Hospital $40 550 $56 838 $40 043
Other specified, classifiable ED $6897 $6609 $6537
Hospital $43 067 $39 961 $63 521 $48 203
Other specified, NEC ED
Hospital $40 694 $51 297 $48 954
Unspecified ED $6997 $7176
Hospital $44 179 $56 071 $50 569
Adverse effects ED
Hospital $39 254 $65 409
E-code missing ED $6776 $7017
Hospital $41 812 $43 541
All mechanisms ED $7150 $5890 $6921 $6106 $7961 $7004 $6884
Hospital $41 082 $34 958 $52 787 $32 255 $65 525 $43 215 $41 605
Number of records, survey-weighted number, and simple mean, SE and 95% CI for all cost estimates reported in online supplementary tables S1 and S3.
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Blank cells indicate average cost not calculated due to low number of observations (zero visits or admissions or relative SE >30% or SE=0) in the data source. ‘All mechanisms’ model controlled for
mechanism. ‘All intents’ model controlled for intent. ‘All’/’All’ model controlled for both.
Source data: Healthcare Cost and Utilization Project National Inpatient Sample and Nationwide Emergency Department Sample. Injury classification in this table based on the ICD-9-CM E-code matrix
(www.cdc.gov/nchs/injury/injury_tools.htm).
E-code, External Cause of Injury code; ED, emergency department; ICD-9-CM, International Classification of Diseases, Ninth Revision, Clinical Modification; NEC, not elsewhere classifiable; SE,
Standard error.
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Table 2
Adjusted mean cost of ED visits and admissions for fatal injuries by body region and nature of injury (total n=40 650 survey-weighted)
Body region Fatality
location Fracture Internal Open
wound Blood
vessels Contusion or
superficial Crush Burns unspecified
System-
wide and
late effects All nature of
injury
Head and neck Traumatic brain
injury ED $7001 $6986 $9141
Hospital $44 739 $40 273 $42 545
Other head, face,
neck ED $6735 $7044 $5608
Hospital $43 473 $44 642 $50 111 $43 217 $32 886 $73 042
Total ED $5843 $5954 $5597 $5937 $6373
Hospital $42 274 $38 586 $41 984 $47 074 $40 455 $31 912 $41 345
Spine and back Spinal cord ED
Hospital $42 284 $44 007 $44 731
Vertebral column ED $6341
Hospital $36 799 $39 685
Total ED $6353
Hospital $36 846 $42 494 $40 710
Torso Torso ED $7400 $6937 $6644 $7362 $6821 $8374
Hospital $35 514 $44 941 $45 456 $36 863 $44 722 $47 001
Extremities Upper
extremities ED $6577 $5671
Hospital $36 332 $45 049 $52 325
Lower
extremities ED $7125 $6818
Hospital $35 123 $33 378 $45 280 $38 832
Total ED $6334 $5583 $5965
Hospital $34 151 $38 660 $46 554 $33 368 $42 562 $39 682
Unclassifiable by
site Other or multiple ED $6540 $6818 $5643
Hospital $42 684 $95 295
System-wide ED $6861 $4764
Hospital $50 300 $32 934
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Body region Fatality
location Fracture Internal Open
wound Blood
vessels Contusion or
superficial Crush Burns unspecified
System-
wide and
late effects All nature of
injury
Total ED $5343 $5749 $5659 $4915
Hospital $40 850 $46 534 $34 123
All All body regions ED $7656 $8695 $6759 $10 289 $6419 $6693 $5872 $4782 $6885
Hospital $41 517 $43 047 $52 886 $63 067 $41 660 $68
670 $61 036 $55 398 $33 081 $41 541
Number of records, survey-weighted number, and simple mean, SE and 95% CI for all cost estimates reported in online supplementary tables S2 and S4.
Blank cells indicate average cost not calculated due to low number of observations (zero visits or admissions or relative SE >30% or SE=0) in the data source. Some nature of injury categories not shown in
this table due to no data: dislocation, sprains and strains, amputations, nerves. ‘All body regions’ model controlled for body region. ‘All nature of injury’ model controlled for nature of injury. ‘All’/’All’
model controlled for both.
Source data: Healthcare Cost and Utilization Project National Inpatient Sample and Nationwide Emergency Department Sample. Injury classification in this table based on the ICD-9-CM Barell matrix
(www.cdc.gov/nchs/injury/injury_tools.htm). ED, emergency department; ICD-9-CM, International Classification of Diseases, Ninth Revision, Clinical Modification; SE, Standard error.
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Table 3
Estimated 12-month attributable cost of medical care following emergency department treatment for all patients with non-fatal injuries by mechanism and
intent (n=818 053 injury; n=3 975 125 control)
Mechanism Unintentional Self-inflicted Assault Undetermined Other Unknown All intents
Cut/pierce $3119 $17 320 $17 709 $3435 $3322
Drowning/submersion $12 940 $13 355
Fall $9399 $5406 $9399
Fire/burn $7260 $14 002 $7431
Fire/flame $11 552 $12 325
Hot object/substance $6200 $6224
Firearm $22 805 $37 435 $21 030 $24 859
Machinery $5340 $5340
Motor vehicle traffic $9403 $9408
Occupant $7396 $7396
Motorcyclist $20 415 $20 415
Pedal cyclist $14 193 $14 193
Pedestrian $19 440 $19 440
Unspecified motor vehicle $12 054 $12 054
Other pedal cyclist $6109 $6109
Other pedestrian $9484 $9484
Other transport $11 089 $11 090
Natural/environmental $5838 $5833
Bites and stings $3307 $3307
Overexertion $5251 $5251
Poisoning $9723 $17 563 $13 521 $12 783
Struck by/against $3989 $6828 $10 293 $4146
Suffocation $8331 $19 579 $8904
Other specified, classifiable $4185 $4670 $1698 $4207
Other specified, NEC $5295 $11 121 $6294 $5508 $5411
Unspecified $7032 $26 868 $9047 $8746 $7434
Adverse effects $15 428 $15 428
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Mechanism Unintentional Self-inflicted Assault Undetermined Other Unknown All intents
E-code missing $6508 $6508
All mechanisms $6712 $18 331 $7460 $10 217 $13 967 $6508 $6658
Number of records, survey-weighted number, and simple mean and 95% CI for all cost estimates demonstrated in online supplementary table 5 S5.
Blank cells indicate average cost not calculated due to low number of observations (<21 patients with injury) in the data source. ‘All mechanisms’ model controlled for mechanism. ‘All intents’ model
controlled for intent. ‘All’/’All’ model controlled for both.
Source data: MarketScan (Inpatient Services, Inpatient Admissions, Outpatient Services, Outpatient Pharmaceutical Claims). Injury classification in this table based on the ICD-9-CM E-code matrix
(www.cdc.gov/nchs/injury/injury_tools.htm).
E-code, External Cause of Injury code; ICD-9-CM, International Classification of Diseases, Ninth Revision, Clinical Modification; NEC, not elsewhere classifiable.
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Table 4
Estimated 12-month attributable cost of medical care following emergency department treatment for all patients with non-fatal injuries by body region
and nature of injury (n=818 053 injury; n=3 975 125 control)
Body region Body
region Fracture dislocation
Sprains
and
strains Internal Open
wound Amputations Blood
vessels
Contusion
or
superficial Crush Burns Nerves Unspecified
System-
wide
and late
effects
All
nature
of
injury
Head and
neck Traumatic
brain $40 454 $7832 $9339
injury
Other
head, face, $14 334 $4697 $8767 $3790 $14
693 $4497 $11
034 $6379 $6058 $4948
neck
Total $18 751 $4697 $8767 $7832 $3790 $14
693 $4497 $11
034 $4849 $6058 $5565
Spine and
back Spinal cord $80 172 $34 546 $51
317
Vertebral
column $30 584 $22 263 $5080 $7311
Total $30 957 $22 263 $5080 $34 546 $7395
Torso Torso $19 254 $10 055 $4711 $35 223 $6424 $6306 $11
219 $6232 $8906
Extremities Upper
extremities $9936 $6010 $4214 $3416 $8531 $11
505 $4143 $2775 $4961 $9259 $4305 $5853
Lower
extremities $16 075 $13 393 $5035 $4202 $46 251 $14
161 $5397 $5829 $8894 $6419 $7218
Total $12 128 $7535 $4760 $3668 $10 025 $11
011 $4767 $3429 $5912 $9259 $5336 $6468
Unclassifiable
by site Other or
multiple $11 590 $12 502 $4990 $11 707 $6721 $4438 $5918 $3893 $7620 $6694
System-
wide $7630 $7630
Total $11 590 $12 502 $4990 $11 707 $6721 $4438 $5918 $3893 $7620 $7630 $7407
All body
regions All body
regions $13 856 $7597 $4878 $9297 $3856 $9876 $20
129 $4892 $3465 $7395 $7365 $5869 $7630 $6587
Number of records (patients with injury and control enrollees), and simple mean and 95% CI for all cost estimates demonstrated in online supplementary table 6.
Blank cells indicate average cost not calculated due to low number of observations (<21 patients with injury) in the data source. ‘All nature of injury’ model controlled for nature of injury. ‘All body
regions’ model controlled for body region of injury. ‘All/All’ model controlled for nature and body region of injury.
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Source data: MarketScan (Inpatient Services, Inpatient Admissions, Outpatient Services, Outpatient Pharmaceutical Claims). Injury classification in this table based on the ICD-9-CM Barell matrix
(www.cdc.gov/nchs/injury/injury_tools.htm). ICD-9-CM, International Classification of Diseases, Ninth Revision, Clinical Modification.
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