Related Experiment Video
Updated: Nov 14, 2025
07:30
A Test Bed to Examine Helmet Fit and Retention and Biomechanical Measures of Head and Neck Injury in Simulated Impact
Published on: September 21, 2017
9.1K
Comparison of injuries in multiple and single event crashes
Sophia K Tushak1, Timothy L McMurry1,2, Sang-Hyun Lee1
1Center for Applied Biomechanics, University of Virginia, Charlottesville, Virginia.
Traffic Injury Prevention
|March 10, 2021
Summary
Occupants in multiple event (ME) crashes face higher injury risks than those in single event (SE) crashes. A prior less severe crash increases injury severity in a subsequent, more severe crash event.
Area of Science:
- Biomechanics and injury prevention
- Traffic safety research
- Automotive engineering
Background:
- Understanding occupant injury risk in multi-event (ME) crashes is crucial for improving vehicle safety.
- Previous research has not fully elucidated the specific injury risks associated with a sequence of crash events.
Purpose of the Study:
- To compare injury risks for occupants in ME crashes (less severe followed by more severe event) versus occupants in similar single event (SE) crashes.
- To analyze injury patterns across detailed body regions and assess the influence of crash sequencing on injury severity.
Main Methods:
- Matched analysis of 1,663 ME occupants and 3,217 SE occupants from NASS-CDS (2000-2015) using conditional logistic regression.
- Finite element (FE) simulations with human surrogate models (GHBMC, Hybrid III) under low- and high-speed conditions to replicate ME and SE crash scenarios.
Main Results:
- ME occupants exhibited higher Maximum Abbreviated Injury Scale (MAIS) 2+ and MAIS 3+ injury risks compared to SE occupants.
- Eleven of 27 injury groups showed significantly higher risk in ME crashes (FDR < 0.1), particularly to the head, thorax, lumbar spine, shoulder, and lower extremity.
- FE simulations indicated increased head and thorax injury risk (up to 5-fold) in ME scenarios due to greater displacements.
Conclusions:
- A preceding less severe crash event increases occupant injury risk in a subsequent, more severe crash compared to experiencing only the severe event.
- Potential contributing factors include occupant out-of-positioning and altered interaction with safety systems (e.g., airbags) after the initial event.
- Findings underscore the importance of considering crash event sequencing in the development of advanced automotive safety systems.
More Related Videos
Related Concept Videos
01:20Comparing the Survival Analysis of Two or More Groups
399
Survival analysis is a cornerstone of medical research, used to evaluate the time until an event of interest occurs, such as death, disease recurrence, or recovery. Unlike standard statistical methods, survival analysis is particularly adept at handling censored data—instances where the event has not occurred for some participants by the end of the study or remains unobserved. To address these unique challenges, specialized techniques like the Kaplan-Meier estimator, log-rank test, and...
399
01:19Types of Collisions - II
9.1K
When two or more objects collide with each other, they can stick together to form one single composite object (after collision). The total mass of the object after the collision is the sum of the masses of the original objects, and it moves with a velocity dictated by the conservation of momentum. Although the system's total momentum remains constant, the kinetic energy decreases, and thus such a collision is an inelastic collision. Most of the collisions between objects in daily life are...
9.1K
01:05Collisions in Multiple Dimensions: Introduction
6.0K
It is far more common for collisions to occur in two dimensions; that is, the initial velocity vectors are neither parallel nor antiparallel to each other. Let's see what complications arise from this. The first idea is that momentum is a vector. Like all vectors, it can be expressed as a sum of perpendicular components (usually, though not always, an x-component and a y-component, and a z-component if necessary). Thus, when the statement of conservation of momentum is written for a...
6.0K
01:21Introduction to Test of Independence
2.7K
In statistics, the term independence means that one can directly obtain the probability of any event involving both variables by multiplying their individual probabilities. Tests of independence are chi-square tests involving the use of a contingency table of observed (data) values.
The test statistic for a test of independence is similar to that of a goodness-of-fit test:
The test statistic for a test of independence is similar to that of a goodness-of-fit test:
2.7K
01:08Determination of Expected Frequency
2.4K
Suppose one wants to test independence between the two variables of a contingency table. The values in the table constitute the observed frequencies of the dataset. But how does one determine the expected frequency of the dataset? One of the important assumptions is that the two variables are independent, which means the variables do not influence each other. For independent variables, the statistical probability of any event involving both variables is calculated by multiplying the individual...
2.4K
01:13Multiple Comparison Tests
4.2K
Multiple comparison test, abbreviated as MCT, is a post hoc analysis generally performed after comparing multiple samples with one or more tests. An MCT will help identify a significantly different sample among multiple samples or a factor among multiple factors.
It would be easy to compare two samples using a significance alpha level of 0.05. In other words, there is only one sample pair to be compared. However, it would be difficult to identify a significantly different sample if the number...
It would be easy to compare two samples using a significance alpha level of 0.05. In other words, there is only one sample pair to be compared. However, it would be difficult to identify a significantly different sample if the number...
4.2K