Academic Journal
View in EDS

Contributing factors to the severity of crash injury and vehicle damage involving Japanese lightweight vehicles (K-car): Considering unobserved heterogeneity.

Bibliographic Details
Title: Contributing factors to the severity of crash injury and vehicle damage involving Japanese lightweight vehicles (K-car): Considering unobserved heterogeneity.
Authors: Wang L; School of Traffic and Transportation Engineering, Central South University, Changsha, Hunan 410075, China. Electronic address: 244211023@csu.edu.cn., Lee JJ; School of Traffic and Transportation Engineering, Central South University, Changsha, Hunan 410075, China; Department of Civil, Environmental & Construction Engineering, University of Central Florida, Orlando, FL, USA; School of Civil and Environmental Engineering, Faculty of Engineering, Queensland University of Technology (QUT), Brisbane, QLD 4000, Australia. Electronic address: lizaining@csu.edu.cn., Hu J; School of Traffic and Transportation Engineering, Central South University, Changsha, Hunan 410075, China. Electronic address: Junjie_Hu@csu.edu.cn., Mao S; School of Traffic and Transportation Engineering, Central South University, Changsha, Hunan 410075, China; Department of Environment, Land and Infrastructure Engineering, Politecnico di Torino, Torino 10129, Italy. Electronic address: suyimao@csu.edu.cn.
Source: Journal of safety research [J Safety Res] 2026 Sep; Vol. 98, pp. 40-54. Date of Electronic Publication: 2026 Jun 08.
Publication Type: Journal Article; Research Support, Non-U.S. Gov't
Language: English
Journal Info: Publisher: Pergamon Press Country of Publication: United States NLM ID: 1264241 Publication Model: Print-Electronic Cited Medium: Internet ISSN: 1879-1247 (Electronic) Linking ISSN: 00224375 NLM ISO Abbreviation: J Safety Res Subsets: MEDLINE
Imprint Name(s): Publication: Elmsford, NY : Pergamon Press
Original Publication: [Chicago] National Safety Council.
MeSH Terms: Accidents, Traffic*/statistics & numerical data , Automobiles*/statistics & numerical data , Wounds and Injuries*/epidemiology , Safety*, Japan/epidemiology ; Humans ; Injury Severity Score ; Risk Factors
Abstract: Introduction: This study investigates the safety performance of lightweight vehicles by analyzing the factors influencing injury severity and vehicle damage in Japan.
Method: Likelihood ratio tests were initially employed to validate the temporal stability of the crash data. Subsequently, random parameter bivariate probit models with heterogeneity in means were estimated to account for unobserved heterogeneity and correlations between crash outcomes.
Results: An out-of-sample prediction analysis reveals a quantifiable structural safety gap for lightweight vehicles, which is often masked by the risk-compensatory behaviors of older drivers. The model demonstrates a significant negative correlation between the injury severities of the two drivers involved, indicating a "zero-sum" energy transfer effect, while the weak injury-damage correlation suggests a "decoupling" effect attributable to modern passive safety designs. Key findings indicate that injury severity is predominantly exacerbated by environmental factors like adverse weather and slippery surfaces, whereas vehicle damage is driven by geometric incompatibilities with road features like curbs.
Conclusions and Practical Applications: As the first study to apply this advanced modeling framework to lightweight vehicle safety, our findings offer evidence-based insights for optimizing emergency medical protocols, structural reinforcement standards, and driver assistance systems.
(Copyright © 2026 National Safety Council and Elsevier Ltd. All rights reserved.)
Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper.
Contributed Indexing: Keywords: Crash severity; Lightweight vehicle; Unobserved heterogeneity
Entry Date(s): Date Created: 20260915 Date Completed: 20260915 Latest Revision: 20261006
Update Code: 20261006
DOI: 10.1016/j.jsr.2026.05.017
PMID: 42744492
Database: MEDLINE
FullText Text:
  Availability: 0
CustomLinks:
  – Url: https://www.doi.org/10.1016/j.jsr.2026.05.017?
    Name: ScienceDirect (all content) (s7799221)
    Category: fullText
    Text: View record from ScienceDirect
    MouseOverText: View record from ScienceDirect
  – Url: https://resolver.ebsco.com/c/fiv2js/result?sid=EBSCO:cmedm&genre=article&issn=18791247&ISBN=&volume=98&issue=&date=20260901&spage=40&pages=40-54&title=Journal of safety research&atitle=Contributing%20factors%20to%20the%20severity%20of%20crash%20injury%20and%20vehicle%20damage%20involving%20Japanese%20lightweight%20vehicles%20%28K-car%29%3A%20Considering%20unobserved%20heterogeneity.&aulast=Wang%20L&id=DOI:10.1016/j.jsr.2026.05.017
    Name: Full Text Finder (for New FTF UI) (ns324271)
    Category: fullText
    Text: Full Text Finder
    MouseOverText: Full Text Finder
Header DbId: cmedm
DbLabel: MEDLINE
An: 42744492
AccessLevel: 3
PubType: Academic Journal
PubTypeId: academicJournal
PreciseRelevancyScore: 0
IllustrationInfo
Items – Name: Title
  Label: Title
  Group: Ti
  Data: Contributing factors to the severity of crash injury and vehicle damage involving Japanese lightweight vehicles (K-car): Considering unobserved heterogeneity.
– Name: Author
  Label: Authors
  Group: Au
  Data: <searchLink fieldCode="AU" term="%22Wang+L%22">Wang L</searchLink>; School of Traffic and Transportation Engineering, Central South University, Changsha, Hunan 410075, China. Electronic address: 244211023@csu.edu.cn.<br /><searchLink fieldCode="AU" term="%22Lee+JJ%22">Lee JJ</searchLink>; School of Traffic and Transportation Engineering, Central South University, Changsha, Hunan 410075, China; Department of Civil, Environmental & Construction Engineering, University of Central Florida, Orlando, FL, USA; School of Civil and Environmental Engineering, Faculty of Engineering, Queensland University of Technology (QUT), Brisbane, QLD 4000, Australia. Electronic address: lizaining@csu.edu.cn.<br /><searchLink fieldCode="AU" term="%22Hu+J%22">Hu J</searchLink>; School of Traffic and Transportation Engineering, Central South University, Changsha, Hunan 410075, China. Electronic address: Junjie_Hu@csu.edu.cn.<br /><searchLink fieldCode="AU" term="%22Mao+S%22">Mao S</searchLink>; School of Traffic and Transportation Engineering, Central South University, Changsha, Hunan 410075, China; Department of Environment, Land and Infrastructure Engineering, Politecnico di Torino, Torino 10129, Italy. Electronic address: suyimao@csu.edu.cn.
– Name: TitleSource
  Label: Source
  Group: Src
  Data: <searchLink fieldCode="JN" term="%221264241%22">Journal of safety research</searchLink> [J Safety Res] 2026 Sep; Vol. 98, pp. 40-54. <i>Date of Electronic Publication: </i>2026 Jun 08.
– Name: TypePub
  Label: Publication Type
  Group: TypPub
  Data: Journal Article; Research Support, Non-U.S. Gov't
– Name: Language
  Label: Language
  Group: Lang
  Data: English
– Name: TitleSource
  Label: Journal Info
  Group: Src
  Data: <i>Publisher: </i><searchLink fieldCode="PB" term="%22Pergamon+Press%22">Pergamon Press </searchLink><i>Country of Publication: </i>United States <i>NLM ID: </i>1264241 <i>Publication Model: </i>Print-Electronic <i>Cited Medium: </i>Internet <i>ISSN: </i>1879-1247 (Electronic) <i>Linking ISSN: </i><searchLink fieldCode="IS" term="%2200224375%22">00224375 </searchLink><i>NLM ISO Abbreviation: </i>J Safety Res <i>Subsets: </i>MEDLINE
– Name: PublisherInfo
  Label: Imprint Name(s)
  Group: PubInfo
  Data: <i>Publication</i>: Elmsford, NY : Pergamon Press<br /><i>Original Publication</i>: [Chicago] National Safety Council.
– Name: SubjectMESH
  Label: MeSH Terms
  Group: Su
  Data: <searchLink fieldCode="MM" term="%22Accidents%2C+Traffic%22">Accidents, Traffic*</searchLink>/<searchLink fieldCode="MM" term="%22Accidents%2C+Traffic+statistics+%26+numerical+data%22">statistics & numerical data</searchLink> <br /><searchLink fieldCode="MM" term="%22Automobiles%22">Automobiles*</searchLink>/<searchLink fieldCode="MM" term="%22Automobiles+statistics+%26+numerical+data%22">statistics & numerical data</searchLink> <br /><searchLink fieldCode="MM" term="%22Wounds+and+Injuries%22">Wounds and Injuries*</searchLink>/<searchLink fieldCode="MM" term="%22Wounds+and+Injuries+epidemiology%22">epidemiology</searchLink> <br /><searchLink fieldCode="MM" term="%22Safety%22">Safety*</searchLink><br /><searchLink fieldCode="MH" term="%22Japan%22">Japan</searchLink>/<searchLink fieldCode="MH" term="%22Japan+epidemiology%22">epidemiology</searchLink> ; <searchLink fieldCode="MH" term="%22Humans%22">Humans</searchLink> ; <searchLink fieldCode="MH" term="%22Injury+Severity+Score%22">Injury Severity Score</searchLink> ; <searchLink fieldCode="MH" term="%22Risk+Factors%22">Risk Factors</searchLink>
– Name: Abstract
  Label: Abstract
  Group: Ab
  Data: Introduction: This study investigates the safety performance of lightweight vehicles by analyzing the factors influencing injury severity and vehicle damage in Japan.<br />Method: Likelihood ratio tests were initially employed to validate the temporal stability of the crash data. Subsequently, random parameter bivariate probit models with heterogeneity in means were estimated to account for unobserved heterogeneity and correlations between crash outcomes.<br />Results: An out-of-sample prediction analysis reveals a quantifiable structural safety gap for lightweight vehicles, which is often masked by the risk-compensatory behaviors of older drivers. The model demonstrates a significant negative correlation between the injury severities of the two drivers involved, indicating a "zero-sum" energy transfer effect, while the weak injury-damage correlation suggests a "decoupling" effect attributable to modern passive safety designs. Key findings indicate that injury severity is predominantly exacerbated by environmental factors like adverse weather and slippery surfaces, whereas vehicle damage is driven by geometric incompatibilities with road features like curbs.<br />Conclusions and Practical Applications: As the first study to apply this advanced modeling framework to lightweight vehicle safety, our findings offer evidence-based insights for optimizing emergency medical protocols, structural reinforcement standards, and driver assistance systems.<br /> (Copyright © 2026 National Safety Council and Elsevier Ltd. All rights reserved.)
– Name: Abstract
  Label: Competing Interests
  Group: Ab
  Data: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper.
– Name: SubjectMinor
  Label: Contributed Indexing
  Group:
  Data: <i>Keywords: </i>Crash severity; Lightweight vehicle; Unobserved heterogeneity
– Name: DateEntry
  Label: Entry Date(s)
  Group: Date
  Data: <i>Date Created: </i>20260915 <i>Date Completed: </i>20260915 <i>Latest Revision: </i>20261006
– Name: DateUpdate
  Label: Update Code
  Group: Date
  Data: 20261006
– Name: DOI
  Label: DOI
  Group: ID
  Data: 10.1016/j.jsr.2026.05.017
– Name: AN
  Label: PMID
  Group: ID
  Data: 42744492
PLink https://search.ebscohost.com/login.aspx?direct=true&site=eds-live&db=cmedm&AN=42744492
RecordInfo BibRecord:
  BibEntity:
    Identifiers:
      – Type: doi
        Value: 10.1016/j.jsr.2026.05.017
    Languages:
      – Code: eng
        Text: English
    PhysicalDescription:
      Pagination:
        StartPage: 40
    Subjects:
      – SubjectFull: Japan epidemiology
        Type: general
      – SubjectFull: Humans
        Type: general
      – SubjectFull: Injury Severity Score
        Type: general
      – SubjectFull: Risk Factors
        Type: general
      – SubjectFull: Accidents, Traffic statistics & numerical data
        Type: general
      – SubjectFull: Automobiles statistics & numerical data
        Type: general
      – SubjectFull: Wounds and Injuries epidemiology
        Type: general
      – SubjectFull: Safety
        Type: general
    Titles:
      – TitleFull: Contributing factors to the severity of crash injury and vehicle damage involving Japanese lightweight vehicles (K-car): Considering unobserved heterogeneity.
        Type: main
  BibRelationships:
    HasContributorRelationships:
      – PersonEntity:
          Name:
            NameFull: Wang L
      – PersonEntity:
          Name:
            NameFull: Lee JJ
      – PersonEntity:
          Name:
            NameFull: Hu J
      – PersonEntity:
          Name:
            NameFull: Mao S
    IsPartOfRelationships:
      – BibEntity:
          Dates:
            – D: 01
              M: 09
              Text: 2026 Sep
              Type: published
              Y: 2026
          Identifiers:
            – Type: issn-electronic
              Value: 1879-1247
          Numbering:
            – Type: volume
              Value: 98
          Titles:
            – TitleFull: Journal of safety research
              Type: main
ResultId 1