Exhibit 1.
Characteristics of the intervention and control populations in 2010, before and after propensity score weighting
| Patient Characteristic | Before Weighting
|
After Weighting a
|
||
|---|---|---|---|---|
| Intervention population (n=77,756) | Control population (n=68,117) | Intervention population | Control population | |
|
| ||||
| Male (%) | 43.8% | 43.3% | 43.5% | 43.5% |
| Age group (years, %): | ||||
| <65 | 13.6% | 13.0% | 13.2% | 13.2% |
| 65–69 | 25.6% | 25.5% | 25.6% | 25.6% |
| 70–74 | 19.8% | 20.5% | 20.2% | 20.2% |
| 75–79 | 16.2% | 16.6% | 16.4% | 16.4% |
| 80–84 | 12.7% | 12.8% | 12.8% | 12.8% |
| ≥85 | 12.1% | 11.6% | 11.8% | 11.8% |
| Race/ethnicity (%): | ||||
| White | 89.8% | 86.0% | 88.1% | 88.1% |
| Black | 8.4% | 11.7% | 9.9% | 9.9% |
| Hispanic | 0.8% | 0.9% | 0.8% | 0.8% |
| Other | 1.0% | 1.4% | 1.2% | 1.2% |
| Disabled (%) b | 18.2% | 17.6% | 17.8% | 17.8% |
| Enrolled in Medicaid (%) c | 8.6% | 8.4% | 8.4% | 8.4% |
| End-stage renal disease (%) | 0.8% | 1.1% | 0.9% | 0.9% |
| Number of Chronic Conditions d | 5.24 | 5.30 | 5.26 | 5.26 |
Propensity score weights were used to balance the observed characteristics of patients in the intervention and control populations in each study year. Therefore, the effective sample sizes of the intervention and control populations in 2010 were 36,010 patients. After weighting, there were no differential changes on observed characteristics between the intervention and control populations from the pre-intervention to the post-intervention periods (see Appendix Exhibit 6).
Disability was the patient’s original reason for Medicare eligibility.
Dually enrolled in Medicare and Medicaid (excluding recipients of partial Medicaid coverage through the Qualified Medicare Beneficiary, Specified Low-Income Medicare Beneficiary, or Qualified Individual programs).
Assessed from the Medicare Chronic Conditions Data Warehouse (CCW), which includes indicators for the following 27 chronic conditions: Alzheimer’s disease, Alzheimer’s disease and related disorders or senile dementia, anemia, asthma, atrial fibrillation, benign prostatic hyperplasia, breast cancer, cataract, chronic kidney disease, chronic obstructive pulmonary disease, colorectal cancer, depression, diabetes, endometrial cancer, glaucoma, heart failure, hip or pelvic fracture, hyperlipidemia, hypertension, hypothyroidism, ischemic heart disease, lung cancer, osteoporosis, prostate cancer, acute myocardial infarction, rheumatoid arthritis, and stroke or transient ischemic attack. We assessed the presence of chronic conditions reported for each patient prior to the study year. Regression analyses were adjusted for indicators for each of these 27 chronic conditions as well as the patient’s count of chronic conditions (in unit increments from 2-8 conditions versus ≥ 9 conditions).
Source: Authors’ analyses of fee-for-service Medicare claims for 2010.