Development of the STAR Evaluation System for Football Helmets: Integrating Player Head Impact Exposure and Risk of Concussion
In contrast to the publicly available data on the safety of automobiles, consumers have no analytical mechanism to evaluate the protective performance of football helmets. The objective of this article is to fill this void by introducing a new equation that can be used to evaluate helmet performance by integrating player head impact exposure and risk of concussion. The Summation of Tests for the Analysis of Risk (STAR) equation relates on-field impact exposure to a series of 24 drop tests performed at four impact locations and six impact energy levels. Using 62,974 head acceleration data points collected from football players, the number of impacts experienced for one full season was translated to 24 drop test configurations. A new injury risk function was developed from 32 measured concussions and associated exposure data to assess risk of concussion for each impact. Finally, the data from all 24 drop tests is combined into one number using the STAR formula that incorporates the predicted exposure and injury risk for one player for one full season of practices and games. The new STAR evaluation equation will provide consumers with a meaningful metric to assess the relative performance of football helmets.
KeywordsConcussion Mild traumatic brain injury Acceleration Risk Exposure HITS Impact
The authors gratefully acknowledge our sponsors for this research, including the National Highway Traffic Safety Administration and National Institutes of Health (National Institute for Child Health and Human Development) (Contract No. R01HD048638).
- 9.Dick, R., M. S. Ferrara, J. Agel, R. Courson, S. W. Marshall, M. J. Hanley, and F. Reifsteck. Descriptive epidemiology of collegiate men’s football injuries: national collegiate athletic association injury surveillance system, 1988–1989 through 2003–2004. J. Athl. Train. 42:221–233, 2007.PubMedGoogle Scholar
- 10.Domenico, L. D., and G. Nusholtz. Comparison of Parametric and Non-Parametric Methods for Determining Injury Risk. SAE Technical Paper Series, SAE 2003-01-1362, 2003.Google Scholar
- 12.Duma, S. M., and S. Rowson. Every newton hertz: a macro to micro approach to investigating brain injury. Conf. Proc. IEEE Eng. Med. Biol. Soc. 1:1123–1126, 2009.Google Scholar
- 15.Gadd, C. W. Use of a weighted-impulse criterion for estimating injury hazard. In: Proceedings of the 10th Stapp Car Crash Conference, SAE 660793, 1966.Google Scholar
- 21.Guskiewicz, K. M., J. P. Mihalik, V. Shankar, S. W. Marshall, D. H. Crowell, S. M. Oliaro, M. F. Ciocca, and D. N. Hooker. Measurement of head impacts in collegiate football players: relationship between head impact biomechanics and acute clinical outcome after concussion. Neurosurgery 61:1244–1253, 2007.PubMedCrossRefGoogle Scholar
- 23.Hackney, J. R., and C. J. Kahane. The New Car Assessment Program: Five Star Rating System and Vehicle Safety Performance Characteristics. SAE Technical Paper Series, SAE 851245, 1995.Google Scholar
- 26.Kent, R. W., and J. R. Funk. Data Censoring and Parametric Distribution Assignment in the Development of Injury Risk Functions from Biomechanical Data. SAE Technical Paper Series, SAE 2004-01-0317, 2004.Google Scholar
- 27.King, A. I., K. H. Yang, L. Zhang, W. Hardy, and D. C. Viano. Is head injury caused by linear or angular acceleration? In: Proceedings of the International Research Conference on the Biomechanics of Impact (IRCOBI), 2003.Google Scholar
- 34.NOCSAE. Standard test method and equipment used in evaluating the performance characteristics of protective headgear/equipment. National Operating Committee on Standards for Athletic Equipment: NOCSAE DOC (ND)001-08m10, 2009.Google Scholar
- 37.Pellman, E. J., J. W. Powell, D. C. Viano, I. R. Casson, A. M. Tucker, H. Feuer, M. Lovell, J. F. Waeckerle, and D. W. Robertson. Concussion in professional football: epidemiological features of game injuries and review of the literature–part 3. Neurosurgery 54:81–94, 2004; discussion 6.PubMedCrossRefGoogle Scholar
- 45.Takhounts, E. G., S. A. Ridella, V. Hasija, R. E. Tannous, J. Q. Campbell, D. Malone, K. Danelson, J. Stitzel, S. Rowson, and S. Duma. Investigation of traumatic brain injuries using the next generation of simulated injury monitor (simon) finite element head model. Stapp Car Crash J. 52:1–31, 2008.PubMedGoogle Scholar