## 2 Methods
### Vehicle Models  
Two types of vehicle models were used. First, the publicly available 2011 Honda Accord FE model was used for crash pulse generation during car-to-car crash simulations (Figure 2a) [59]. Interior and occupant restraint systems were converted into MADYMO environment to create an MB version of the vehicle model for occupant simulations. To improve computational efficiency, all parts except the airbag and seatbelt were modeled as rigid bodies using facet elements (Figure 2b). The MB vehicle model consisted of an instrument panel (IP), a right-side front door, a center console, a front-row passenger seat, a passenger airbag (PAB), and a 3-point seatbelt with a shoulder belt load limiter and a pre-tensioner. The MADYMO Accord vehicle model was validated through comparison with a real-world dummy crash test (NHTSA test number: MD5303). Responses of the small female H3 dummy model were compared with those from the crash test data (Figure 3).  
\begin{table}
\begin{tabular}{l l l l} \hline \hline
**Type** & **Body Region** & **Test Condition** & **References** \\ \hline \multirow{4}{*}{Component} & Shoulder & Lateral impact & ISO9790 [46] \\  & & Lateral impact & [PERSON] et al., 2010 [47] \\  & & Lateral impact & [PERSON] et al., 2004 [48] \\  & Abdomen & Frontal impact & [PERSON] et al., 1986 [49] \\  & Abdomen & Lateral oblique impact & [PERSON] et al., 1989 [45] \\  & Pelvis & Lateral impact & [PERSON] et al., 1989 [45] \\ \hline Whole-body & Whole-body & Braking 50 km/h (1 g) & OM4 IS project [13; 34; 35] \\ \hline \hline \end{tabular}
\end{table}
Table 1: _Cont._  
\begin{table}
\begin{tabular}{l l l} \hline \hline \multicolumn{1}{c}{**Body Region**} & \multicolumn{1}{c}{**Injury Metrics (or Predictor)**} & **AIS Level** \\ \hline Skull & HIC15 ([PERSON] et al., 1999 [50]) & 2+ \\ Brain & Damage ([PERSON] et al., 2019 [51]) & 2+ \\ \hline Thorax & Chest compression ([PERSON] and [PERSON], 2005 [52]) & 3+ \\ \hline Abdomen & Abdomen compression ([PERSON] et al., 2020 [53]) & 3+ \\ \hline Cervical spine & Nij (frontal) ([PERSON] et al., 1999 [50]) & 2+ \\ Lumbar spine & Compressive axial force ([PERSON] et al., 2012 [54]) & 2+ \\ \hline Hip & Resultant force ([PERSON] et al., 2009 [55]) & 2+ \\ Femoral condyle & Compressive axial force ([PERSON] et al., 2010 [56]) & 3+ \\ Tibial plateau & Compressive axial force ([PERSON] et al., 2001 [57]) & 2+ \\ Ankle & Axial load at distal tibia ([PERSON] et al., 2002 [58]) & 2+ \\ \hline \hline \end{tabular}
\end{table}
Table 2: Injury metrics for injury risk prediction.  
Figure 2: A mid-sized sedan interior model for pre-crash and crash simulations. (**a**) LS-Dyna accord model and (**b**) MADYMO vehicle interior model.  
A generic passenger airbag model was used in the MADYMO simulation due to the unavailability of detailed information on the OEM airbag from the crash test. While the generic model did not reproduce the initial spike in head acceleration observed at around 35 ms in the test data, the simulation captured the overall trend well during the later phase. Overall, the MADYMO simulation results showed a good correlation with the test data. A comparison of injury metrics is provided in Supplementary Materials S1.