Table 2. Standardized Differences of Balancing Variables used for PSM Matching.

Standardized differences for each balancing variable used during propensity score modeling. Values less than 0.10 indicate balance was achieved between treatment groups.

Balancing Variable	Standardized Difference
Admitted from emergency department	0.032
Age group	0.002
Elixhauser comorbidity score	0.004
Expected payer	0.027
Injury severity score	0.025
Surgical approach	0.033
Known spinal cord injury	0.029
Urban-rural continuum	0.012