This content is not included in
your SAE MOBILUS subscription, or you are not logged in.
Considerations for Head-Injury Categorization via NASS Analysis
Technical Paper
2017-01-1430
ISSN: 0148-7191, e-ISSN: 2688-3627
This content contains downloadable datasets
Annotation ability available
Sector:
Language:
English
Abstract
The present study had three objectives: (1) define a reasonable number of categories to bin head injuries, (2) develop an overarching risk function to estimate head-injury probability based on injury probabilities pertaining to those subordinate categories, and (3) assess the fidelity of both the overarching function and approximations to it. To achieve these objectives, we used real-world data from the National Automotive Sampling System (NASS), pertaining to adult drivers in full-engagement frontal crashes. To provide practical value, we factored the proposed US New Car Assessment Program (US NCAP) and the corresponding Request for Comments from the government. Finally, the NASS data stratifications included three levels of injury (AIS1+, AIS2+, AIS3+), two levels of restraint (properly-belted, unbelted), and two eras based on driver-airbag fitment (Older Vehicles, Newer Vehicles).
For Objective 1, three categories were studied (“brain-related,” “bone-related,” and/or “otherwise-related”), as well as the overarching category (“head”). The following trends for category-based injury rates (IR) were noted: (a) more than 84% of head-injury cases involved only one of the injury categories, (b) IRAIS3+ < IRAIS2+ < IRAIS1+, (c) IRbelted < IRunbelted, and (d) IRNewerVehicles < IROlderVehicles. We noted otherwise-related injury was primary to AIS1+ studies, but brain-related injury was primary to AIS2+ and AIS3+ studies. Therefore, the AIS3+ head-risk assessment in the proposed US NCAP will likely improve most by improving the estimation of brain-related injury.
For Objective 2, a three-category overarching risk function was assumed, based on subordinate injury probabilities: max(Pbrain, Pbone, Pother). For each level of injury (AIS1+, AIS2+, and AIS3+), this function was evaluated for 88 possible bins, and cross-correlated with the direct-estimate Phead. Each resulting regression-line slope nearly equaled 1.0, with R2=0.96 for AIS1+ injury, R2=0.98 for AIS2+ injury, and R2=0.99 for AIS3+ injury.
For Objective 3, the methodology used of the second objective was repeated for one- and two-category functions. We noted that, as category count decreased, fidelity degraded. However, the fidelity of the two-category function yielded nearly identical fidelity as the three-category function. Pertinent to the proposed US NCAP, the best-available two-category function for AIS3+ assessment would involve brain- and bone-related assessment.
Recommended Content
Citation
Laituri, T. and Henry, S., "Considerations for Head-Injury Categorization via NASS Analysis," SAE Technical Paper 2017-01-1430, 2017, https://doi.org/10.4271/2017-01-1430.Data Sets - Support Documents
Title | Description | Download |
---|---|---|
Unnamed Dataset 1 | ||
Unnamed Dataset 2 | ||
Unnamed Dataset 3 | ||
Unnamed Dataset 4 | ||
Unnamed Dataset 5 | ||
Unnamed Dataset 6 | ||
Unnamed Dataset 7 | ||
Unnamed Dataset 8 | ||
Unnamed Dataset 9 |
Also In
References
- Cormier , J. and Duma , S. 2009 Epidemiology of Facial Fractures in Automotive Collisions Annals of the Advancement of Automotive Medicine 53 169 176
- Cormier , J 2009 Epidemiology and Biomechanical Analysis of Facial Fractures PhD Dissertation Virginia Polytechnic Institute and State University
- Hershman , L. 2001 The U.S. New Car Assessment Program (NCAP): Past, Present, and Future International Technical Conference on Enhanced Safety Vehicles, Paper No. 390
- King , A. , Yang , K. , Zhang , L. , Hardy , W. , and Viano , D. 2003 Is Head Injury caused by Linear or Angular Acceleration? IRCOBI Conference 1 11
- Laituri , T. , El-Jawahri , R. , Henry , S. , and Sullivan , K. Field-based Assessments of Various AIS2+ Head Risk Curves for Frontal Impact SAE Technical Paper 2015-01-1437 2015 10.4271/2015-01-1437
- Laituri , T. , Henry , S. , El-Jawahri , R. , Muralidharan , N. , Li , G. , and Nutt , M. 2015b Derivation of a Provisional, Age-dependent, AIS2+ Thoracic Risk Curve for the THOR50 Test Dummy via Integration of NASS Cases, PMHS Tests, and Simulation Data Stapp Car Crash Journal 59 131 176
- Laituri , T. , Henry , S. , Pline , K. , Li , G. , Frankstein , M. , and Weerappuli , P. 2016 New Risk Curves for NHTSA’s Brain Injury Criterion (BrIC): Derivations and Assessments,“ Stapp Car Crash Journal 60 301 362
- Mueller , B. , MacAlister , A. , Nolan , J. , and Zuby , D. 2015 Comparison of HIC and BrIC Head Injury Risk in IIHS Frontal Crash Tests to Real-world Head Injuries Proceedings of 24th Enhanced Safety of Vehicles (ESV) Conference Paper 15-0272 Gothenburg, Sweden
- NHTSA/GESAC 2005 THOR-NT User’s Manual: 50% Male Frontal Dummy Report No. GESAC-05-02, Revision 2005.1 March 2005
- NHTSA 2007 Consumer Information: New Car Assessment Program Docket No. NHTSA-2006-26555, Federal Register 73 134 July 11 2008 40042
- NHTSA 2015 Request for Comments Docket No. NHTSA-2015-0119, New Car Assessment Program Dec. 8 2015
- Salottolo , K. , Settell , A. , Uribe , P. , Akin , S. , Denetta , S. , O’Neal , E. , Mains , C. , and Bar-Rr , D. 2009 The Impact of the AIS 2005 Revision on Injury Severity Scores and Clinical Outcome Measures Injury 40 999 1003
- Viano , D. and Parenteau , C. 2015 Concussion, Diffuse Axonal Injury, and AIS4+ Head Injury in Motor Vehicle Crashes Traffic Injury Prevention 16 8 747 753