Table 3.

Adjusted Rate Ratios and Difference-in-Difference in Visit Rates by Diabetes Status and Medicaid Expansion Status, Accelerating Data Value Across a National Community Health Center Network Clinical Data Research Network from 2012 to 2015*

Patient InformationNonexpansionExpansionExpansion vs Nonexpansion
Post-ACA vs Pre-ACAPost-ACA vs Pre-ACA
RR (95% CI)RR (95% CI)DD Ratio (95% CI)
Uninsured
    Diabetes0.85 (0.76–0.94)0.44 (0.39–0.49)0.52 (0.44–0.60)
    Prediabetes0.86 (0.76–0.95)0.48 (0.42–0.54)0.56 (0.47–0.65)
    No diabetes0.82 (0.74–0.89)0.47 (0.42–0.52)0.57 (0.50–0.65)
Medicaid
    Diabetes0.99 (0.92–1.07)1.57 (1.43–1.71)1.58 (1.40–1.77)
    Prediabetes1.07 (0.98–1.16)1.71 (1.53–1.88)1.59 (1.38–1.80)
    No diabetes1.00 (0.91–1.09)1.60 (1.46–1.73)1.60 (1.40–1.80)
Privately insured
    Diabetes2.77 (1.79–3.75)1.10 (0.96–1.25)0.40 (0.25–0.55)
    Prediabetes3.17 (2.03–4.31)1.10 (0.90–1.31)0.35 (0.21–0.49)
    No diabetes2.70 (2.02–3.38)1.06 (0.94–1.18)0.39 (0.28–0.50)
Other public
    Diabetes0.79 (0.66–0.92)1.08 (0.97–1.20)1.37 (1.10–1.64)
    Prediabetes0.84 (0.65–1.03)1.04 (0.86–1.22)1.24 (0.89–1.59)
    No diabetes0.73 (0.59–0.87)0.90 (0.77–1.04)1.24 (0.94–1.53)
Total visit
    Diabetes1.00 (0.93–1.07)1.05 (0.99–1.09)1.04 (0.95–1.14)
    Prediabetes1.10 (1.00–1.19)1.15 (1.09–1.20)1.05 (0.94–1.16)
    No diabetes0.98 (0.91–1.06)1.03 (0.98–1.08)1.05 (0.95–1.15)
Primary care
    Diabetes0.98 (0.91–1.06)1.03 (0.98–1.07)1.05 (0.96–1.14)
    Prediabetes1.08 (0.98–1.17)1.14 (1.08–1.19)1.05 (0.95–1.16)
    No diabetes0.96 (0.88–1.04)1.02 (0.96–1.07)1.06 (0.95–1.16)
Preventive Care
    Diabetes1.26 (1.03–1.50)1.12 (1.02–1.23)0.89 (0.71–1.08)
    Prediabetes1.35 (1.13–1.58)1.31 (1.19–1.42)0.96 (0.79–1.14)
    No diabetes1.20 (1.04–1.37)1.11 (1.01–1.20)0.92 (0.77–1.07)
Glucose testing
    Diabetes1.22 (1.11–1.32)1.14 (1.09–1.20)0.94 (0.84–1.04)
    Prediabetes1.24 (1.13–1.35)1.23 (1.17–1.30)0.99 (0.89–1.09)
    No diabetes1.20 (1.09–1.31)1.29 (1.21–1.37)1.07 (0.95–1.19)
HbA1c screening
    Diabetes1.46 (1.35–1.56)1.26 (1.21–1.31)0.87 (0.80–0.94)
    Prediabetes1.76 (1.56–1.95)2.00 (1.80–2.19)1.14 (0.87–1.40)
    No diabetes1.70 (1.45–1.96)2.26 (1.97–2.56)1.33 (1.09–1.57)
  • ACA, Affordable Care Act; RR, rate ratio; CI, confidential interval; DD, difference-in-difference testing post-period versus pre-period in expansion versus non-expansion states.

  • * Nonexpansion states: FL, KS, MO, and NC; expansion states: CA, HI, MD, NM, OH, OR, RI, WA, and WI. Visit rates were by dividing the number of visits in a given interval (ie, pre-ACA or post-ACA period) by the total number of adult patients seen in a clinic over the study period, scaled to 1000 patients per month. Boldfaced values indicate statistically significant difference, P < .05. Total visits: CPT 99201 to 99205, 99212 to 99215, 99241 to 99245, 99381 to 99384, 99385 to 99387, or 99391 to 99397 with MD, DO, NP, PA, midwife, or resident with no specialty listed. Generalized estimating equation Poisson models adjusted for clinic-level demographic distributions (sex, age, federal poverty level, primary language, race, and ethnicity), state-level factors (marketplace type, 2013 minimum wage and unemployment rates, 2013 uninsured rate), and 2013 state-level CHCs diabetes prevalence (https://bphc.hrsa.gov/datareporting/index.html) clustered by facility to account for within-facility correlation. DD estimates obtained from linear combinations of time × expansion status interaction.