State Variation in Quality Outcomes and Disparities in Outcomes in Community Health Centers

Abstract

Background: Prior studies have reported that community health centers perform as well as other sites of care, despite serving more vulnerable patient populations. However, there is little prior study of geographic variation in quality outcomes and disparities in outcomes in this setting. Quantifying geographic variation is important so as to target quality improvement efforts and funding and to learn from states where total quality is highest and racial/ethnic disparities are lowest.

Objectives: To estimate between-state variation in hypertension, diabetes, and pregnancy outcomes and racial/ethnic disparities in these outcomes for health center patients.

Methods: Using data on all US health centers from 2010 to 2014 (N=1047 health centers/year, or 21.2 million patients in 2014), we used linear regression models to estimate adjusted quality outcomes and racial/ethnic disparities in quality outcomes by state for hypertension control, diabetes control, and normal birthweight.

Results: We found wide variation in both outcomes and racial/ethnic disparities in outcomes between states for patients seen at health centers. For instance, between states, the mean proportion of patients with hypertension control ranged from 58% to 70% for white patients, from 49% to 64% for black patients, and from 53% to 74% for Hispanic patients (P<0.001). Racial/ethnic disparities in outcomes ranged from negative or nonsignificant in some states to positive in others.

Conclusions: Wide variation in health center patient outcomes and disparities in outcomes is observed between states. This variation suggests that policymakers should target funding and interventions to underperforming states, and identify determinants of high quality in higher performing states.

Figure 1. State Variation in Hypertension Control for White versus Black Patients, 2010–2014

As you move further up the y-axis, average hypertension control rates increase for white patients and as you move further down the x-axis, average hypertension control rates increase for black patients. A 45-agree angle line dissects the graph, where states close to or on the line exhibit no aggregate disparity between the two racial/ethnic groups; the further above the line a state appears, the larger the disparity in that state. Each state estimate represents the adjusted, population-weighted mean rate from 2010–2014 across all health centers in the state. All state estimates have p<0.001. All state estimates, including 95% confidence intervals, in addition to analogous figures for diabetes control and normal birthweight, are included in the Supplemental Digital Content (eTable 4, eTable 6, eTable 8).

Figure 2. State Variation in Hypertension Control for White versus Hispanic Patients, 2010–2014

As you move further up the y-axis, average hypertension control rates increase for white patients and as you move further down the x-axis, average hypertension control rates increase for Hispanic patients. A 45-agree angle line dissects the graph, where states close to or on the line exhibit no aggregate disparity between the two racial/ethnic groups; the further above the line a state appears, the larger the disparity in that state. Each state estimate represents the adjusted, population-weighted mean rate from 2010–2014 across all health centers in the state. All state estimates have p<0.001. All state estimates, including 95% confidence intervals, in addition to analogous figures for diabetes control and normal birthweight, are included in the Supplemental Digital Content (eTable 4, eTable 6, eTable 8).