ORIGINAL ARTICLE

National mandatory motorcycle helmet laws may save $2.2 billion annually: An inpatient and value of statistical life analysis Anahita Dua, MD, MS, MBA, Shuyan Wei, Justin Safarik, Courtney Furlough, and Sapan S. Desai, MD, PhD, MBA, Springfield, Illinois

While statistics exist regarding the overall rate of fatalities in motorcyclists with and without helmets, a combined inpatient and value of statistical life (VSL) analysis has not previously been reported. METHODS: Statistical data of motorcycle collisions were obtained from the Centers for Disease Control, National Highway Transportation Safety Board, and Governors Highway Safety Association. The VSL estimate was obtained from the 2002 Department of Transportation calculation. Statistics on helmeted versus nonhelmeted motorcyclists, death at the scene, and inpatient death were obtained using the 2010 National Trauma Data Bank. Inpatient costs were obtained from the 2010 National Inpatient Sample. Population estimates were generated using weighted samples, and all costs are reported using 2010 US dollars using the Consumer Price Index. RESULTS: A total of 3,951 fatal motorcycle collisions were reported in 2010, of which 77% of patients died at the scene, 10% in the emergency department, and 13% as inpatients. Thirty-seven percent of all riders did not wear a helmet but accounted for 69% of all deaths. Of those motorcyclists who survived to the hospital, the odds ratio of surviving with a helmet was 1.51 compared with those without a helmet (p G 0.001). Total costs for nonhelmeted motorcyclists were 66% greater at $5.5 billion, compared with $3.3 billion for helmeted motorcyclists (p G 0.001). Direct inpatient costs were 16% greater for helmeted riders ($203,248 vs. $175,006) but led to more than 50% greater VSL generated (absolute benefit, $602,519 per helmeted survivor). CONCLUSION: A cost analysis of inpatient care and indirect costs of motorcycle riders who do not wear helmets leads to nearly $2.2 billion in losses per year, with almost 1.9 times as many deaths compared with helmeted motorcyclists. The per capita cost per fatality is more than $800,000. Institution of a mandatory helmet law could lead to an annual cost savings of almost $2.2 billion. (J Trauma Acute Care Surg. 2015;78: 1182Y1186. Copyright * 2015 Wolters Kluwer Health, Inc. All rights reserved.) LEVEL OF EVIDENCE: Economic analysis, level III. KEY WORDS: Helmet laws; motorcycle helmet laws; cost analysis of helmets; VSL; inpatient costs. BACKGROUND:

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n the 1960s, the US federal government required that states must have universal motorcycle helmet laws to apply for certain highway funds. By the mid-1970s, 47 of the 50 states enacted universal helmet laws. Soon thereafter, the federal government lost its authority to penalize helmet noncompliance, and helmet laws became more lax. As of 2014, 47 states have helmet laws, of which only 19 states have universal helmet laws. The other 28 states have specific helmet laws that extend only to the young (age G 18Y21 years), the inexperienced (instructional permit, or licensed G 1 year), and/or those with little to no medical insurance (G$10,000 for motorcycle-related injuries). Currently, Illinois, Iowa, and New Hampshire have no motorcycle helmet laws.1

Submitted: August 26, 2014, Revised: January 7, 2015, Accepted: January 12, 2015. From the Department of Surgery (A.D., S.W.), Medical College of Wisconsin, Milwaukee, Wisconsin; University of Virginia (J.S.), Charlottesville, Virginia; Department of Surgery (C.F.), University of Texas at Houston, Houston, Texas; and Department of Vascular Surgery (S.S.D.), Southern Illinois University, Springfield, Illinois. This study was part of the poster presentation at 73rd Annual Meeting of American Association for the Surgery of Trauma and Clinical Congress of Acute Care Surgery, September 10Y13, 2014, in Philadelphia, Pennsylvania. Address for reprints: Anahita Dua MD, MS, MBA, Department of Surgery, Medical College of Wisconsin, 8701 Watertown Plank Rd, Milwaukee, WI 53226; email: [email protected] DOI: 10.1097/TA.0000000000000601

Motorcycle helmets have been well documented in preventing life-threatening head injuries, with the incidence of brain injury being sixfold lower in helmeted patients.2 Helmeted patients are significantly less likely to present with a Glasgow Coma Scale (GCS) score of 8 or lower and less likely to die of their injuries.3 The incidence and severity of other anatomic injuries (facial, thoracic, abdominal, genitourinary, limb, and spine) did not differ significantly between helmeted and nonhelmeted riders.2 While statistics exist regarding the overall rate of fatalities in motorcyclists with and without helmets, a combined inpatient and value of statistical life (VSL) analysis has not previously been reported in the motorcycle population regarding the use of helmets. VSL is the overall cost of reducing the average number of deaths by one and can be thought of as the value an individual places on a marginal change in their likelihood of death. There is no universal method for measuring the value of a human life. One commonly used objective method is to evaluate decisions people make regarding their own health and the costs associated with implementing a risk reduction strategy. For example, are they willing to pay for airbags in their car, and how much are they willing to pay based on the risk of death reduction airbags produce? These improvements that correlated with a decrease risk of morbidity and mortality accumulate, and a total dollar amount can be calculated. Given that public policy decisions are frequently J Trauma Acute Care Surg Volume 78, Number 6

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based on dollar amounts people would be willing to pay to reduce certain risks, this VSL approach can be applied to a mortality aversion valuation from riding a motorcycle with or without a helmet. In this case, the ‘‘cost’’ of wearing a helmet is the actual price of the helmet and the cost to the freedom of the individual, while the ‘‘benefit’’ is an improvement in mortality should a collision occur. This is the same type of benefit-cost analysis performed by the Environmental Protection Agency when evaluating whether a new environmental law should be implemented. VSL has also been extensively applied to determine benefits of vaccinations in the US population.4,5 VSL has also been extensively applied to the determination of risk in road safety for motorists in cars.6,7 This article presents a numerical analysis based on data from the 2010 National Trauma Data Bank, 2010 National Inpatient Sample (NIS), and 2002 Department of Transportation calculations of motorcycle collisions in helmeted versus nonhelmeted patients and their associated VSL. We hope to highlight the financial impact of the lack of universal motorcycle helmet laws in the United States. This study aimed to determine the financial impact of mandating the wearing of helmets by law nationally, and we hypothesize that US states that do not have mandatory helmet laws will have a higher economic loss based on a VSL analysis.

PATIENTS AND METHODS

Variable

Value

No. deaths at the scene No. deaths in the ED No. deaths as inpatient Total motorcycle fatalities in 2010

3,056 381 514 3,951

the average number of deaths by one and can be thought of as the value an individual places on a marginal change in their likelihood of death. The VSL is used by the US government when determining public health policy change, implementing new safety measures, and deciding whether to fund a new Medicare/Medicaid measure.9 The actual VSL in 2010 US dollars is $47,040.10 Population estimates were made by means of discharge sampling weights included within the NIS and data published by the US Census Bureau; these estimates were used to adjust for population growth over time. Costs, value, inflation, and future value calculations are reported in 2014 US dollars adjusted using the Consumer Price Index. A 3% discount rate was used for future value calculations, which is the rate used by the US Treasury. An average lifespan of 78.6 years was obtained from the US Census Bureau and used for VSL calculations.9

Patient Selection and Cost Calculation

Data Sources A decision analysis was completed using direct costs and indirect costs. An example of a direct cost is that arising from an inpatient hospitalization along with any inpatient complications. Costs were obtained from the 2010 Nationwide Inpatient Sample. The NIS is a part of the Health Care Utilization Project that is maintained by the Agency for Healthcare Research and Quality.8 It is the largest all-payer inpatient database and includes a stratified 20% random sample of all nonfederal inpatient hospital admissions throughout the United States. Clinical records were obtained with the use of International Classification of DiseasesV9th Rev. E-codes to include only patients involved in motorcycle collisions. Indirect costs were determined as the lost value of a human life due to death arising from a motorcycle collision. A surrogate for this indirect cost is the VSL. The VSL is based on meta-analyses completed by the Environmental Protection Agency using wage data and workplace risk data from the Bureau of Labor Statistics.4,5 It is the overall cost of reducing TABLE 1. Demographics of Patients Who Were Involved in a Motorcycle Collision and Admitted to the Hospital Variable Age, mean (SD), y Female No. chronic conditions, mean (SD) No. diagnoses on record, mean (SD) DRG severity of illness score, mean (SD) DRG mortality risk score, mean (SD) LOS, d Inpatient mortality

TABLE 2. Breakdown of Motorcycle Fatalities and Costs in 2010

Value 40.5 (14.2) 6.8% 1.4 (1.7) 7.2 (4.8) 2.3 (1.0) 1.5 (0.9) 7.0 (4.0Y12.0) 2.6%

Patients were identified using E-codes, and only mortality following motorcycle collisions was evaluated as the single end point. Costs were calculated using cost-to-charge ratios provided by the NIS. All costs are provided in 2014 US dollars adjusted using the Consumer Price Index. Independent variables included demographics and comorbidities. Outcomes reviewed included length of stay (LOS), cost, and inpatient mortality. Patient covariates specifically included age, sex, number of chronic conditions, diagnosis-related group (DRG) mortality score, DRG severity of illness score, LOS, inpatient mortality, and cost. The DRG mortality score and severity of illness score are validated methods of assigning values from 0 to 4 and estimates the risk of inpatient mortality or loss of function.

Decision Analysis and Statistical Analysis Statistical analysis was completed with the use of analysis of variance for continuous variables (i.e., age and costs). The Mann-Whitney U-test was used for comparing total costs and overall value. Data analysis and management were completed with the use of the IBM SPSS software package (SPSS version 22.0, SPSS Inc., Chicago, IL). Statistical significance was set at a level of p G 0.05. Values are presented as mean (SD) or as median with interquartile range in parentheses. LOS is presented a median with interquartile range. The 95% confidence intervals were determined for all cost and value calculations. Odds ratios were calculated using multivariate regression analysis.

RESULTS A total of 3,951 fatal motorcycle collisions were reported in 2010, of which 77% of patients died at the scene, 10% in the

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TABLE 3. Cost Calculations for Loss of Life for All Patients Variable

Value

Direct costs Inpatient cost for survivors per patient Inpatient cost per fatality Indirect costs Average age of patient in motorcycle fatality, y Average lifespan in 2010, y 2010 VSL Lost value from motorcycle fatality per life Total no. motorcycle fatalities in 2010 Total loss from motorcycle fatalities (indirect costs)

$144,756 $233,498 42.0 78.5 $47,040 $1,718,859 3,951 $6,791,213,747

emergency department (ED), and 13% as inpatients. Table 1 details the demographics of patients involved in motorcycle crashes who were admitted to the hospital. There was an inpatient mortality rate among this group of 2.6%. Table 2 details the location of these mortalities (scene, ED, or inpatient). Table 3 depicts the cost calculations for loss of life for all patients regardless of helmet status. Thirty-seven percent of all riders did not wear a helmet but accounted for 69% of all deaths. Of those motorcyclists who survived to the hospital, the odds ratio of surviving with a helmet was 1.51 compared with those without a helmet (p G 0.001). Of the hospitalized patients, 6.5% died following motorcycle collision. A VSL analysis ($47,040 per year) yielded $6.8 billion of indirect losses. Total costs for nonhelmeted motorcyclists were 66% greater at $5.5 billion, compared with $3.3 billion for helmeted motorcyclists (p G 0.001). Direct inpatient costs were 16% greater for helmeted riders ($203,248 vs. $175,006) but led to more than 50% greater VSL generated (absolute benefit, $602,519 per helmeted survivor). The direct and indirect costs related to rehabilitation for trauma following inpatient discharge were determined from a previously published meta-analysis and adjusted for inflation.11 Per capita direct costs for rehabilitation following trauma were $7,212, and indirect costs were $35,182. Patient

disposition was determined using the NIS, and 24.1% of nonhelmeted patients were discharged to another facility for rehabilitation, compared with 20.0% of helmeted patients. Total direct costs for nonhelmeted motorcyclists were $855 million, lower than the $1.2 billion for helmeted motorcyclists. However, this was offset by indirect costs that were more than two times higher for nonhelmeted motorcyclists ($4.7 billion vs. $2.2 billion). Overall costs for nonhelmeted motorcyclists were $5.6 billion, compared with $3.4 billion for helmeted motorcyclists. Table 4 details the mortality and cost breakdown for helmeted versus nonhelmeted motorcyclists.

DISCUSSION Law et al. analyzed factors influencing motorcycle deaths based on data compiled from 25 countries, including the United States, between 1970 and 1999 using a negative binomial model. They proposed that the graphical depiction of the relationship between per capita income and motorcycle deaths is shaped like an upside-down U-curve, with motorcycle deaths being lower with lower per capita income (due to a smaller number of motorcycle owners) and also with higher per capita income (arising from increased concerns about road safety, leading to more road safety legislations). They concluded that helmet laws are negatively associated with motorcycle deaths (p G 0.01), along with other factors such as quality of political institutions, medical care, and technology developments.12 In a well-developed country, such as the United States where the political institution, medical care, and technology are of the highest quality, the next area of improvement would be to improve road safety via increasing universal helmet law awareness across more states. In a more recent study, Law et al. examined factors influencing enactment of motorcycle helmet laws based on data from 31 countries between 1963 and 2002. They identified increased democracy, higher education level, higher per capita income, political stability, and equitable income distribution as leading factors associated with the establishment of more road safety laws.12,13 The efficacy of universal helmet laws was examined by the Centers for Disease Control and Prevention, which

TABLE 4. Mortality and Cost Breakdown for Helmeted versus Nonhelmeted Motorcyclists No Helmet n (%) Death at scene 2,277 (57.6) Death in ED 168 (4.3) Inpatient death 281 (7.1) Hospital survivors 5,127 (39.9) Discharged to facility 1,236 (24.1) Total 7,853 Grand total Cost savings with helmet per year Additional expected survivors if helmet

Direct Cost

Helmet Indirect Cost

N/A $3,913,841,943 $39,227,664 $288,768,312 $65,612,938 $482,999,379 $742,164,012 N/A $8,913,735 $43,485,385 $855,918,349 $4,729,095,019 $5,585,013,368

n (%) 779 (19.7) 213 (5.4) 233 (5.9) 7,728 (60.1) 1,546 (20.0) 8,953

Direct Cost

Indirect Cost

N/A $1,338,991,161 $49,735,074 $366,116,967 $54,405,034 $400,494,147 $1,118,674,368 N/A $11,149,381 $54,391,913 $1,233,963,857 $2,159,994,188 $3,393,958,045

$2,191,055,323 1,461 people

Percent calculations provided are of the subset of patients who died following a motorcycle collision for the first three data rows. The percentages provided for the survivors are of the subset of patients who survived overall following a motorcycle collision.

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reported that states with universal motorcycle helmet laws averaged 12% nonhelmeted fatalities, compared with 64% nonhelmeted fatalities in states with partial helmet laws and 79% nonhelmeted fatalities in states without any helmet laws. In other words, fatally injured riders were five times as likely to not be wearing a helmet in states with partial helmet laws and six times as likely to not be wearing a helmet in states with no helmet laws. These data stress the importance of universal helmet laws in encouraging helmet compliance and in reducing motorcycle fatalities. In addition, based on the National Highway Traffic Safety Administration’s data from 2008 to 2010, the Centers for Disease Control and Prevention calculated that current helmet laws saved $3 billion and estimates that instating universal helmet laws in every state could save an additional $1.4 billion.13Y15 This totals to a savings of $4.4 billion, which is very close to the $4.6 billion projected by our VSL calculations. VSL has been shown to be a useful tool in analyzing investments in road fatality prevention, vaccines-related investments, and cost-effectiveness of a suicide barrier on the Golden Gate Bridge (GGB). Milligan et al.6 proposed a new VSL function for road safety engineering that is applicable to developing countries and compared this function with one that is applicable to developed countries. Their developing country VSL function was based on a meta-analysis of previously established VSL calculations published in Mortality Risk Valuation in Environment, Health and Transport Policies. Furthermore, they suggested that their functions could be applied to other areas of public wellness such as issues related to the environment, health, and cancer. Laxminarayan et al.16 examined the pros and cons of willingness-to-payVa concept based on VSLVagainst standard cost-effectiveness analysis (such as quality-adjusted life years and disability-adjusted life years) in estimating the benefits of vaccine investments. Their studies concluded that VSL can reflect both health benefits and nonhealth benefits (such as economic wellbeing, financial risk protection, and gains in productivity). They argued that VSL can be accurately applied to populations of all income, as long as calculations are weighted based on income distribution. Whitmer and Woods17 used VSL estimates from US highway projects to calculate the cost-benefit of a proposed suicide barrier on the GGB over a 20-year period. They examined GGB suicide rates over seven decades and assumed that the individuals whose suicides were prevented by the GGB barrier will ultimately successfully commit suicide by jumping off other structures (lethality of 98% vs. 47%, respectively), at a suicide rate of 12% to 13% per year. For 20 years, their VSL calculations estimates an average cost per life savings of more than $180,000Vmaking implementation of a suicide barrier on the GGB highly cost-beneficial. A cost analysis of inpatient care and indirect costs of motorcycle riders who do not wear helmets leads to nearly $2.2 billion in losses per year, with almost 1.9 times as many deaths compared with helmeted motorcyclists. The per capita cost per fatality is more than $800,000. Institution of a mandatory helmet law can lead to an annual cost savings of almost $2.2 billion, plus an additional $2.4 billion generated as a result of a VSL calculation for a total of $4.6 billion net gain per year.

Limitations This study is limited by its retrospective design and the use of a large database that does not include follow-up data. As a result, it is not possible to report on compliance of helmet laws before the crash or function status of patients and overall return-to-work status after the crash.

CONCLUSION A cost analysis of inpatient care and indirect costs of motorcycle riders who do not wear helmets leads to an excess of $2.2 billion in losses per year, with almost 1.9 times as many deaths compared with helmeted motorcyclists. The per capita cost per fatality is more than $800,000. Institution of a mandatory helmet law can lead to an annual cost savings of more than $2.2 billion, plus an additional $2.4 billion generated as a result of a VSL calculation for a total of $4.6 billion net gain per year.

AUTHORSHIP All authors contributed to the literature search, study design, data collection, data analysis, data interpretation, writing, and critical revision of this article.

DISCLOSURE The authors declare no conflicts of interest.

REFERENCES 1. Governors Highway Safety Association. Helmet LawsVAugust 2014. Available at: http://www.ghsa.org/html/stateinfo/laws/helmet_laws.html. Accessed August 10, 2014. 2. Bachulis BL, Sangster W, Gorrell GW, Long WB. Patterns of injury in helmeted and nomhelmeted motorcyclists. Am J Surg. 1988;155:708Y711. 3. Gupta A, Jaipuria J, et al. Motorised two-wheeler crash and helmets: injury patterns, severity, mortality and the consequence of gender bias. World J Surg. 2014;38:215Y221. 4. Mrozek J, Taylor L. What determines the value of life? A meta analysis. J Policy Anal Manage. 2002;21(2):253Y270. 5. Viscusi K, Aldy JE. The value of a statistical life: a critical review of market estimates throughout the world. J Risk Uncertainty Springer. 2003;27(1):5Y76. 6. Milligan C, Kopp A, Dahdah S, Montufar J. Value of a statistical life in road safety: a benefit-transfer function with risk-analysis guidance based on developing country data. Accid Anal Prev. 2014;71:236Y247. 7. Hauer E. Computing what the public wants: some issues in road safety cost-benefit analysis. Accid Anal Prev. 2011;43(1):151Y164. 8. Healthcare Cost and Utilization. Available at: http://www.ahrq.gov/research/ data/hcup/index.html. Accessed August 21, 2014. 9. Mortality Risk Evaluation. Available at: http://yosemite.epa.gov/ EE%5Cepa%5Ceed.nsf/webpages/MortalityRiskValuation.html. Accessed December 1, 2014. 10. Valuating Mortality Risk Reductions. Available at: http://yosemite.epa.gov/ee/ epa/eerm.nsf/vwAN/EE-0563-1.pdf/$file/EE-0563-1.pdf. Accessed December 1, 2014. 11. Ma VY, Chan L, Carruthers KJ. Incidence, prevalence, costs, and impact on disability of common conditions requiring rehabilitation in the United States: stroke, spinal cord injury, traumatic brain injury, multiple sclerosis, osteoarthritis, rheumatoid arthritis, limb loss, and back pain. Arch Phys Med Rehabil. 2014;95(5):986Y995.e1.

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12. United States Census Bureau. Available at: http://www.census.gov/. Accessed August 21, 2014. 13. Law TH, Noland RB, Evans AW. Factors associated with the relationship between motorcycle deaths and economic growth. Accid Anal Prev. 2009;41:234Y240. 14. Law TH, Noland RB, Evans AW. Factors associated with the enactment of safety belt and motorcycle helmet laws. Risk Anal. 2013;33(7): 1367Y1378.

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15. Centers for Disease Control and Prevention. Helmet use among motorcyclists who died in crashes and economic cost savings associated with state motorcycle helmet lawsVUnited States, 2008Y2010.. MMWR Morb Mortal Wkly Rep. 2012;61(23):425Y437. 16. Laxminarayan R, Jamison DT, Krupnick AJ, Norheim OF. Valuing vaccines using value of statistical life measures. Vaccine. 2014;32(39):5065Y5070. 17. Whitmer DA, Woods DL. Cost effectiveness of a suicide barrier on the golden gate bridge. Crisis. 2013;32(2):98Y106.

* 2015 Wolters Kluwer Health, Inc. All rights reserved.

Copyright © 2015 Wolters Kluwer Health, Inc. All rights reserved.

National mandatory motorcycle helmet laws may save $2.2 billion annually: An inpatient and value of statistical life analysis.

While statistics exist regarding the overall rate of fatalities in motorcyclists with and without helmets, a combined inpatient and value of statistic...
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