TABLE 2—
Results of Difference-in-Difference Estimation of Healthcare Expenditures and Utilization: Health Care Spending and Use Under the Affordable Care Act Expansion, United States, 2011–2012
| Total Health Care Spending |
Share of Out-of-Pocket Payment |
Any Use |
|||||||
| Model 1, Coef (95% CI) | Model 2, Coef (95% CI) | Model 3, Coef (95% CI) | Model 1, Coef (95% CI) | Model 2, Coef (95% CI) | Model 3, Coef (95% CI) | Model 1, OR (95% CI) | Model 2, OR (95% CI) | Model 3, OR (95% CI) | |
| Year 2008–2009 (before the ACA expansion; Ref) | 1.00 | 1.00 | 1.00 | 1.00 | 1.00 | 1.00 | 1.00 | 1.00 | 1.00 |
| Year 2011–2012 (after the ACA expansion) | 0.09 (–0.09, 0.28) | 0.14 (–0.05, 0.33) | 0.14 (–0.04, 0.33) | 0.00 (–0.03, 0.03) | 0.00 (–0.03, 0.03) | 0.00 (–0.03, 0.03) | 1.10 (0.81, 1.51) | 1.09 (0.78, 1.53) | 1.09 (0.77, 1.53) |
| White, aged 27–30 y (Ref) | 1.00 | 1.00 | 1.00 | 1.00 | 1.00 | 1.00 | 1.00 | 1.00 | 1.00 |
| African American, aged 27–30 y | −0.18 (–0.54, 0.18) | −0.37** (–0.65, –0.10) | −0.33* (–0.62, –0.04) | −0.08** (–0.13, –0.03) | −0.06** (–0.1, –0.02) | −0.06** (–0.10, –0.02) | 0.71 (0.47, 1.10) | 0.84 (0.51, 1.38) | 0.83 (0.51, 1.37) |
| Latino, aged 27–30 y | −0.41** (–0.67, −0.15) | −0.44*** (–0.71, –0.18) | −0.45*** (–0.70, –0.19) | 0.01 (–0.04, 0.05) | 0.00 (–0.04, 0.04) | 0.00 (–0.04, 0.04) | 0.51*** (0.36, 0.73) | 0.63* (0.43, 0.92) | 0.63 (0.43, 0.91) |
| Other races/ethnicities, aged 27–30 y | −0.31 (–0.66, 0.05) | −0.45* (–0.79, –0.12) | −0.42** (–0.75, –0.08) | 0.01 (–0.08, 0.10) | 0.01 (–0.07, 0.09) | 0.01 (–0.07, 0.09) | 1.04 (0.58, 1.88) | 0.82 (0.44, 1.53) | 0.81 (0.43, 1.51) |
| White, aged 19–26 y | 0.00 (–0.19, 0.19) | −0.03 (–0.19, 0.14) | 0.00 (–0.16, 0.16) | 0.00 (–0.03, 0.03) | 0.01 (–0.02, 0.04) | 0.01 (–0.02, 0.04) | 1.20 (0.86, 1.68) | 1.17 (0.83, 1.65) | 1.20 (0.85, 1.69) |
| African American, aged 19–26 y | −0.17 (0.42, 0.09) | −0.25* (–0.48, –0.02) | −0.18 (–0.41, 0.04) | −0.08*** (–0.12, –0.03) | −0.05 (–0.08, –0.01) | −0.05** (–0.09, –0.01) | 0.62** (0.43, 0.87) | 0.68* (0.47, 1.00) | 0.70 (0.48, 1.03) |
| Latino, aged 19–26 y | −0.23 (–0.49, 0.03) | −0.20 (–0.50, 0.11) | −0.17 (–0.46, 0.13) | −0.01 (–0.05, 0.03) | −0.00 (–0.04, 0.04) | −0.00 (–0.04, 0.04) | 0.61** (0.44, 0.84) | 0.75 (0.53, 1.06) | 0.75 (0.53, 1.06) |
| Other races/ethnicities, aged 19–26 y | −0.46* (–0.83, –0.10) | −0.50* (–0.92, –0.09) | −0.58*** (–0.93, –0.24) | −0.02 (–0.08, 0.04) | −0.01 (–0.07, 0.06) | −0.01 (–0.07, 0.06) | 0.82 (0.49, 1.37) | 0.82 (0.5, 1.34) | 0.81 (0.50, 1.32) |
| Interaction terms | |||||||||
| White, aged 19–26 y × year 2011–2012 | −0.19 (–0.45, 0.08) | −0.27* (–0.51, –0.02) | −0.25* (–0.49, –0.01) | −0.02 (–0.07, 0.02) | −0.01 (–0.05, 0.02) | −0.01 (–0.05, 0.02) | 0.93 (0.62, 1.41) | 0.88 (0.57, 1.36) | 0.88 (0.57, 1.36) |
| African American, aged 19–26 y × year 2011–2012 | −0.25 (–0.57, 0.08) | −0.35* (–0.65, –0.05) | −0.33* (–0.63, –0.03) | −0.02 (–0.07, 0.04) | −0.01 (–0.05, 0.04) | −0.01 (–0.05, 0.04) | 1.06 (0.66, 1.70) | 1.02 (0.61, 1.71) | 1.02 (0.61, 1.71) |
| Latino, aged 19–26 y × year 2011–2012 | −0.23 (–0.6, 0.14) | −0.33 (–0.75, 0.10) | −0.33 (–0.74, 0.09) | −0.05* (–0.11, 0.00) | −0.04 (–0.09, 0.01) | −0.04 (–0.09, 0.01) | 0.96 (0.64, 1.44) | 0.86 (0.56, 1.30) | 0.87 (0.57, 1.32) |
| Other races/ethnicities, aged 19–26 y × year 2011–2012 | 0.07 (–0.41, 0.56) | 0.21 (–0.45, 0.88) | 0.36 (–0.28, 1.00) | 0.00 (–0.08, 0.08) | 0.00 (–0.07, 0.07) | 0.00 (–0.07, 0.07) | 0.80 (0.41, 1.56) | 0.70 (0.37, 1.35) | 0.73 (0.38, 1.41) |
| African American, aged 27–30 y × year 2011–2012 | −0.25 (–0.68, 0.19) | −0.14 (–0.53, 0.24) | −0.17 (–0.57, 0.24) | 0.01 (–0.05, 0.07) | −0.01 (–0.06, 0.05) | −0.01 (–0.06, 0.05) | 0.88 (0.51, 1.52) | 0.84 (0.45, 1.58) | 0.83 (0.44, 1.55) |
| Latino, aged 27–30 y × year 2011–2012 | 0.40 (–0.03, 0.84) | 0.37 (–0.03, 0.77) | 0.36 (–0.02, 0.75) | −0.01 (–0.08, 0.05) | 0.00 (–0.06, 0.05) | 0.00 (–0.06, 0.05) | 1.38 (0.84, 2.25) | 1.32 (0.78, 2.22) | 1.33 (0.79, 2.24) |
| Other races/ethnicities, aged 27–30 y × year 2011–2012 | 0.10 (–0.31, 0.50) | 0.12 (–0.30, 0.54) | 0.14 (–0.29, 0.58) | −0.03 (–0.13, 0.07) | −0.02 (–0.09, 0.08) | −0.02 (–0.09, 0.08) | 0.64 (0.32, 1.27) | 0.69 (0.33, 1.46) | 0.70 (0.33, 1.50) |
Note. ACA = Affordable Care Act; CI = confidence interval; Coef = coefficient; OR = odds ratio. We used the conceptual framework of Andersen social behavioral model to select the covariates that were associated with health care expenditures. Model 1 = covariates included predisposition factors (i.e., race/ethnicity, gender, marital status, US-born, and interview language); model 2 = model 1 + enabling factors (i.e., education, family income, health care access, urban/rural, and US Census region); model 3 = model 2 + clinical need factors (i.e., self-reported physical and mental health). Full sets of results are omitted for brevity but are available upon request. Multivariate logistic regressions were estimated for any use of physician visit, prescription drug, emergency department visit, and hospital inpatient use. The coefficients of interaction terms of race/ethnicity or age with year indicator were not significant. Results of these regressions are omitted for brevity but are available upon request. All the estimates are nationally representative.
*P < .05; **P < .01; ***P < .001.