Fig. 3

Adjusted mean initial procedure hospital charges (95% CIs) for single-level lumbar fusion surgeries only were significantly lower with V-CBA versus rhBMP-2. **P < 0.0001. Multivariate regression models were adjusted with the following confounding factors as covariates: race, ethnicity, Charlson comorbidity index, health insurance status, initial admission type, initial admission source, initial discharge status, cage insertion, hospital size, hospital teaching status, hospital population served, and hospital region