Exhibit 2. Covariate Adjusted Difference in Differences in Mean Annualized Medicare Expenditures between the PGP Intervention Group and the Comparison Group—Demonstration Period Yearly Average.
Estimated Demonstration Savings | Standard Error | P-Value | ||
---|---|---|---|---|
Medicare Expenditures, Pooled PGPs | –$171 | $22 | <0.001 | |
Medicare Expenditures by PGP | ||||
PGP 1 | 323 | 79 | <0.001 | |
PGP 2 | –188 | 64 | 0.003 | |
PGP 3 | –229 | 94 | 0.015 | |
PGP 4 | 87 | 74 | 0.244 | |
PGP 5 | –310 | 59 | <0.001 | |
PGP 6 | –818 | 53 | <0.001 | |
PGP 7 | –26 | 102 | 0.798 | |
PGP 8 | –142 | 69 | 0.041 | |
PGP 9 | 21 | 49 | 0.675 | |
PGP 10 | 120 | 91 | 0.191 | |
Medicare Expenditures by Cost Components | ||||
Inpatient, Facility | –228 | 18 | <0.001 | |
Hospital Inpatient | –176 | 16 | <0.001 | |
Skilled Nursing Facility | –68 | 8 | <0.001 | |
Outpatient/Professional | 25 | 12 | 0.043 | |
Hospital Outpatient | 85 | 7 | <0.001 | |
Physician/Supplier | –39 | 7 | <0.001 | |
Home Health | –22 | 3 | <0.001 | |
Durable Medical Equipment | 0 | 3 | 0.934 | |
Medicare Expenditures by Subpopulations | ||||
Chronic Conditions | ||||
Cancer | –181 | 90 | 0.044 | |
Congestive heart failure | –687 | 105 | <0.001 | |
Diabetes | –456 | 58 | <0.001 | |
Chronic obstructive pulmonary disease | –522 | 87 | <0.001 | |
Acute ischemic heart disease | –602 | 221 | 0.006 | |
Stroke | –775 | 190 | <0.001 | |
Vascular disease | –535 | 95 | <0.001 | |
Any of 7 above conditions | –337 | 39 | <0.001 | |
Medicare/Medicaid dual eligibility | –90 | 67 | 0.177 | |
Aged but originally entitled to Medicare by disability | –361 | 108 | 0.001 | |
End stage renal disease | 497 | 663 | 0.454 | |
Currently entitled to Medicare by disability | 65 | 67 | 0.331 | |
Upper 10% risk score | –1,922 | 190 | <0.001 | |
Upper 25% risk score | –1,254 | 100 | <0.001 | |
Hospitalized | –402 | 82 | <0.001 |
NOTES: Estimates are derived from multivariate regression models, including demographic and geographic covariates, pre-existing trends, and the risk score.
Regression estimates are weighted by each person/year’s inverse propensity score and the fraction of each year eligible for Medicare.
A negative value for demonstration savings indicates a savings, a positive value a dis-savings.
The Physician/Supplier cost component includes physician/professional expenditures in the inpatient setting.
SOURCE: Authors’ analysis of 2001–2010 Medicare administrative data.