Racial disparities in receiving total hip/knee replacement surgery: the effect of hospital admission sources.

Using a nationally-representative inpatient care dataset (the HCUP National Inpatient Sample from 2002 to 2007) we examined racial disparities in receiving total hip replacement (THR) and total knee replacement (TKR) surgeries. Multivariable logistic regression models revealed that racial minorities were significantly less likely to receive THR or TKR than Whites, controlling for patients' hospital admission source and hospital characteristics. Employing Blinder-Oaxaca decomposition techniques, we found that observed difference in population characteristics explained 55%-67% and 78% of the racial disparities in THR and TKR, respectively. Differences in patients' hospital admission source emerged as the major individual factor associated with these disparities, explaining 57%-77% of racial disparities in THR and 26%-50% of racial disparities in TKR. This study suggests that substantive racial and ethnic disparities exist in utilization of THR and TKR surgery. Observed population characteristics accounted for most of these differences, with hospital admission source being the key factor.