title: Comparing the effects of age, BMI and gender on severe injury (AIS 3+) in motor-vehicle crashes.
abstract: BACKGROUND
  The effects of age, body mass index (BMI) and gender on motor vehicle crash (MVC) injuries are not well understood and current prevention efforts do not effectively address variability in occupant characteristics.
  
  
  OBJECTIVE
  (1) Characterize the effects of age, BMI and gender on serious-to-fatal MVC injury. (2) Identify the crash modes and body regions where the effects of occupant characteristics on the numbers of occupants with injury is largest, and thereby aid in prioritizing the need for human surrogates that represent different types of occupant characteristics and adaptive restraint systems that consider these characteristics.
  
  
  METHODS
  Multivariate logistic regression was used to model the effects of occupant characteristics (age, BMI, gender), vehicle and crash characteristics on serious-to-fatal injuries (AIS 3+) by body region and crash mode using the 2000-2010 National Automotive Sampling System (NASS-CDS) dataset. Logistic regression models were applied to weighted crash data to estimate the change in the number of annual injured occupants with AIS 3+ injury that would occur if occupant characteristics were limited to their 5th percentiles (age≤17 years old, BMI≤19kg/m(2)) or male gender.
  
  
  RESULTS
  Limiting age was associated with a decrease in the total number of occupants with head [8396, 95% CI 6871-9070] and thorax injuries [17,961, 95% CI 15,960-18,859] across all crash modes, decreased occupants with spine [3843, 95% CI 3065-4242] and upper extremity [3578, 95% CI 1402-4439] injuries in frontal and rollover crashes and decreased abdominal [1368, 95% CI 1062-1417] and lower extremity [4584, 95% CI 4012-4995] injuries in frontal impacts. The age effect was modulated by gender with older females more likely to have thorax and upper extremity injuries than older males. Limiting BMI was associated with 2069 [95% CI 1107-2775] fewer thorax injuries in nearside crashes, and 5304 [95% CI 4279-5688] fewer lower extremity injuries in frontal crashes. Setting gender to male resulted in fewer occupants with head injuries in farside crashes [1999, 95% CI 844-2685] and fewer thorax [5618, 95% CI 4212-6272], upper [3804, 95% CI 1781-4803] and lower extremity [2791, 95% CI 2216-3256] injuries in frontal crashes. Results indicate that age provides the greater relative contribution to injury when compared to gender and BMI, especially for thorax and head injuries.
  
  
  CONCLUSIONS
  Restraint systems that account for the differential injury risks associated with age, BMI and gender could have a meaningful effect on injury in motor-vehicle crashes. Computational models of humans that represent older, high BMI, and female occupants are needed for use in simulations of particular types of crashes to develop these restraint systems.
authors: University of Michigan Injury Center, Ann Arbor, MI, United States; University of Michigan Department of Emergency Medicine, Ann Arbor, MI, United States; Addiction Research Center, Department of Psychiatry, University of Michigan, Ann Arbor, MI. Electronic address: cartpatr@med.umich.edu.
authors: Patrick M
authors: PM
authors: Carter
authors: University of Michigan Injury Center, Ann Arbor, MI, United States; University of Michigan Transportation Research Institute, Ann Arbor, MI, United States.
authors: Carol A C
authors: CA
authors: Flannagan
authors: University of Michigan Injury Center, Ann Arbor, MI, United States; University of Michigan Transportation Research Institute, Ann Arbor, MI, United States.
authors: Matthew P
authors: MP
authors: Reed
authors: University of Michigan Injury Center, Ann Arbor, MI, United States; University of Michigan Department of Emergency Medicine, Ann Arbor, MI, United States; Department of Health Behavior and Health Education, University of Michigan School of Public Health, Ann Arbor, MI, United States.
authors: Rebecca M
authors: RM
authors: Cunningham
authors: University of Michigan Injury Center, Ann Arbor, MI, United States; University of Michigan Department of Emergency Medicine, Ann Arbor, MI, United States; University of Michigan Transportation Research Institute, Ann Arbor, MI, United States; University of Michigan Department of Biomedical Engineering, Ann Arbor, MI, United States.
authors: Jonathan D
authors: JD
authors: Rupp
mesh_terms: D015998:Abbreviated Injury Scale; D000063:Accidents, Traffic / Q000401:mortality / Q000706:statistics & numerical data*; D000293:Adolescent; D000328:Adult; D000367:Age Factors; D000368:Aged; D000369:Aged, 80 and over; D015992:Body Mass Index; D006259:Craniocerebral Trauma / Q000145:classification / Q000453:epidemiology*; D005260:Female; D006801:Humans; D016015:Logistic Models; D008297:Male; D008875:Middle Aged; D015999:Multivariate Analysis; D009765:Obesity / Q000453:epidemiology*; D050177:Overweight / Q000453:epidemiology; D012622:Seat Belts / Q000706:statistics & numerical data*; D012737:Sex Factors; D013851:Thinness / Q000453:epidemiology*; D013898:Thoracic Injuries / Q000145:classification / Q000453:epidemiology*; D014947:Wounds and Injuries / Q000145:classification / Q000453:epidemiology; D055815:Young Adult
keywords: Age; Body mass index; Gender; Motor vehicle crash; Unintentional injury