Associations Between 2014 Accountable Care Organization (ACO) Savings Rate and Beneficiary, ACO, and Service Area Characteristics
| Unadjusted | Adjusted | |||
|---|---|---|---|---|
| Coeff. | CI | Coeff. | CI | |
| Service Area Social Deprivation index | ||||
| Quartile 1 (least deprived) | Reference category | Reference category | ||
| Quartile 2 | −1.32 | [−2.74, 0.10] | −1.06 | [−2.42, 0.31] |
| Quartile 3 | −1.40 | [−2.97, 0.18] | −2.68 | [−4.23, −1.14] |
| Quartile 4 (most deprived) | 0.05 | [−1.44, 1.55] | −2.29 | [−3.97, −0.61] |
| Organization characteristics | ||||
| Number of assigned beneficiaries | ||||
| <10,000 | Reference category | |||
| 10,000∼29,999 | −0.55 | [−1.78, 0.69] | ||
| ≥30,000 | −0.68 | [−2.23, 0.87] | ||
| Entry Year | ||||
| 2012 | Reference category | |||
| 2013 | −1.12 | [−2.41, 0.18] | ||
| 2014 | −1.85 | [−3.01, −0.69] | ||
| Region | ||||
| Northeast | Reference category | |||
| Midwest | 1.26 | [−0.22, 2.74] | ||
| South | 2.44 | [0.76, 4.12] | ||
| West | −1.78 | [−3.62, 0.07] | ||
| Track 2 | 4.43 | [2.29, 6.58] | ||
| Historical benchmark in quartiles | ||||
| Quartile 1 | Reference category | |||
| Quartile 2 | 1.27 | [−0.06, 2.6] | ||
| Quartile 3 | 3.31 | [1.81, 4.81] | ||
| Quartile 4 | 5.07 | [2.96, 7.17] | ||
| % PCP | 0.00 | [−0.03, 0.03] | ||
| Beneficiary characteristics | ||||
| % Aged 85 and older | −0.26 | [−0.51, 0.00] | ||
| % Female | 0.11 | [−0.18, 0.41] | ||
| % White | 0.03 | [−0.03, 0.08] | ||
| % Aged dual eligibles | 0.05 | [−0.02, 0.13] | ||
| % Disabled | 0.08 | [−0.01, 0.17] | ||
| HCC score | −2.95 | [−13.09, 7.19] | ||
| N | 320 | |||
CI, confidence interval; HCC, Hierarchical Condition Category; PCP, primary care physician.
Sources: Accountable Care Organizations (ACOs) were identified using the 2014 Shared Savings Program (SSP) ACO Provider File. Their beneficiaries were identified using the 2014 SSP Beneficiary File. The beneficiary ZIP codes were from the 2014 Master Beneficiary Summary File. ACO savings rate and characteristics were from the 2014 SSP ACO Public Use File. Service area characteristics were from the American Community Survey.
To generate the ACO service area, we summed the number of beneficiaries per ZIP code tabulation area (ZCTA), rank ordered those ZCTAs from most to least, and identified those ZCTAs comprising 70%.
The social deprivation index (SDI) is a measure of social and material deprivation, constructed by combining a variety of established publicly available socioeconomic measures into a composite measure using a latent variable approach. We conducted regression where the savings rate was the dependent variable.