Poplin Gerald S, McMurry Timothy L, Forman Jason L, Ash Joseph, Parent Daniel P, Craig Matthew J, Song Eric, Kent Richard, Shaw Greg, Crandall Jeff
University of Virginia, Center for Applied Biomechanics, United States.
University of Virginia, Center for Applied Biomechanics, United States.
Accid Anal Prev. 2017 Sep;106:122-130. doi: 10.1016/j.aap.2017.05.007. Epub 2017 Jun 9.
The Test Device for Human Occupant Restraint (THOR) 50th percentile male anthropomorphic test device (ATD) aims to improve the ability to predict the risk of chest injury to restrained automobile occupants by measuring dynamic chest deflection at multiple locations. This research aimed to describe the methods for developing a thoracic injury risk function (IRF) using the multi-point chest deflection metrics from the 50th percentile male THOR Metric ATD with the SD-3 shoulder and associating to post-mortem human subjects (PMHS) outcomes that were matched on identical frontal and frontal-oblique impact sled testing conditions. Several deflection metrics were assessed as potential predictor variables for AIS 3+ injury risk, including a combined metric, called PC Score, which was generated from a principal component analysis. A parametric survival analysis (specifically, accelerated failure time (AFT) with Weibull distribution) was assessed in the development of the IRF. Model fit was assessed using various modeling diagnostics, including the area under the receiver operating characteristic curve (AUC). Models based on resultant deflection consistently exhibited improved fit compared to models based on x-axis deflection or chord deflection. Risk functions for the THOR PC Score and C (maximum resultant deflection) were qualitatively equivalent, producing AUCs of 0.857 and 0.861, respectively. Adjusting for the potential confounding effects of age, AFT survival models with C or PC Score as the primary deflection metric resulted in the THOR injury risk models with the best combination of biomechanical appropriateness, potential utility and model fit, and may be recommended as injury predictors.
人体乘员约束测试装置（THOR）第50百分位男性拟人测试装置（ATD）旨在通过测量多个位置的动态胸部变形，提高预测受约束汽车乘员胸部受伤风险的能力。本研究旨在描述使用第50百分位男性THOR Metric ATD与SD-3肩部的多点胸部变形指标来开发胸部损伤风险函数（IRF）的方法，并将其与在相同正面和正面斜向冲击雪橇测试条件下匹配的尸体人类受试者（PMHS）结果相关联。评估了几个变形指标作为AIS 3+损伤风险的潜在预测变量，包括一个通过主成分分析生成的综合指标，称为PC评分。在IRF的开发中评估了参数生存分析（具体来说，具有威布尔分布的加速失效时间（AFT））。使用各种建模诊断方法评估模型拟合，包括接收器操作特征曲线（AUC）下的面积。与基于x轴变形或弦向变形的模型相比，基于合成变形的模型始终表现出更好的拟合。THOR PC评分和C（最大合成变形）的风险函数在定性上是等效的，分别产生0.857和0.861的AUC。调整年龄的潜在混杂效应后，以C或PC评分为主要变形指标的AFT生存模型产生了在生物力学适宜性、潜在效用和模型拟合方面最佳组合的THOR损伤风险模型，可推荐作为损伤预测指标。
