Prediction of brain strain across head impact subtypes using 18 brain injury criteria

Multiple brain injury criteria (BIC) are developed to quickly quantify brain injury risks after head impacts. These BIC originated from different types of head impacts (e.g., sports and car crashes) are widely used in risk evaluation. However, the predictability of the BIC on different types of head impacts has not been evaluated. Physiologically, the brain strain is often considered the key parameter of brain injury. To evaluate the BIC's ability to predict brain strain across five datasets comprising different head impact subtypes, linear regression was used to model 95% maximum principal strain, 95% maximum principal strain at corpus callosum, and cumulative strain damage (15%) on 18 BIC. The results show significant differences in the relationship between BIC and brain strain across datasets, indicating the same BIC value may indicate different brain strain in different head impact subtypes. The accuracy of regression is generally decreasing if the BIC regression models are fit on a dataset with a different head impact subtype rather than on the dataset with the same subtype. Given this finding, this study raises concerns for applying BIC to predict the brain strain for head impacts different from the head impacts on which the BIC was developed.