Although recent research has reported equity gains in the university-level physics classroom, there remains evidence of significant inequities by race. We conducted a series of multiple linear regressions to examine the magnitude of these inequities in introductory mechanics final exam scores. When we followed a common method of grouping students by underrepresented minority (URM) status in our statistical analysis, we found that when controlling for prior knowledge, based on ACT math and physics placement test scores, there was no evidence of racial inequities. However, when we performed the same analysis but replaced URM status with separate groups for each race or ethnicity reported to the university, we found that African American and Asian American students, and to a lesser extent, Hispanic students, underperformed in their physics course relative to their non-Hispanic White American peers, even when controlling for prior knowledge. We conclude that grouping students by URM status may not be sufficient to detect patterns of academic difficulties experienced by specific racial and ethnic groups of students. Furthermore, these results lead us to believe that there is still work to be done at the university level to provide a learning environment supportive of students of all backgrounds.