Table 2. JHU Medicare Capitation Adjustment Model Number 1: The ADG-MDC Model.
| Year 1 Variable | Year 2 Weight (SE) | Label | Population |
|---|---|---|---|
|
| |||
| (Dollars) | (Percent) | ||
| Intercept | 608 (28) | Base Expected Payment | |
| Male | 604 (26) | Male/Female | 39.2 |
| Years Over 65 | 67 (2) | Number of Years Over Age 65 | 10.1 (Mean) |
| Ever Disabled | 1,119 (51) | Ever Received SI Disability | 6.3 |
| Medicaid | 761 (43) | Currently Medicaid Eligible | 9.6 |
| MDC 1 | 1,533 (36) | Nervous System Inpatient Admission | 1.9 |
| MDC 3/4 | 3,237 (46) | Ears, Nose, Throat, Respiratory Systems | 2.9 |
| MDC 5 | 1,897 (79) | Circulatory System | 5.5 |
| MDC 6 | 1,759 (30) | Digestive System | 2.7 |
| MDC 7 | 1,030 (53) | Hepatobilliary System, Pancreas | 0.8 |
| MDC 8 | 1,117 (27) | Musculoskeletal, Connective Tissue | 2.7 |
| MDC 9 | 1,762 (77) | Skin, Subcutaneous Tissue and Breast | 0.7 |
| MDC 10 | 2,938 (43) | Endocrine, Nutritional, Metabolic Systems | 0.8 |
| MDC 11 | 2,526 (116) | Kidney, Urinary Tract | 1.0 |
| MDC 18 | 3,061 (79) | Infectious, Parasitic Diseases | 0.5 |
| MDC 19/20 | 1,957 (32) | Mental Disease, Alcohol, Drug Abuse | 0.7 |
| MDC 21 | 1,882 (29) | Injuries, Poisonings, Burns | 0.2 |
| MDC 23/24 | 1,481 (40) | Health Status Factors, Trauma | 0.5 |
| MDC 25/16/17 | 3,875 (79) | Blood, Immunological, Myeloproliferative Diseases, HIV, AIDS | 0.4 |
| MDC 26 | 3,944 (60) | Transplants | 0.4 |
| VADG 3 | 542 (36) | Time Limited, Major Diagnosis | 15.7 |
| VADG 4 | 734 (64) | Time Limited, Major, Primary Infections | 8.4 |
| VADG 6 | 818 (123) | Asthma | 2.5 |
| VADG 7 | 225 (65) | Likely to Recur, Discrete | 23.6 |
| VADG 9 | 965 (134) | Likely to Recur, Progressive | 6.7 |
| VADG 11 | 1,345 (126) | Chronic Medical, Unstable | 42.0 |
| VADG 16 | 650 (107) | Chronic Specialty, Unstable, Orthopedic | 2.7 |
| VADG 22 | 525 (177) | Injuries/Adverse Effects, Major | 10.0 |
| VADG 23 | 698 (110) | Psychiatric, Time Limited, Minor | 1.2 |
| VADG 25 | 804 (245) | Psychiatric, Persistent or Recurrent, Unstable | 2.8 |
| VADG 27 | 460 (163) | Signs/Symptoms, Uncertain | 20.2 |
| VADG 28 | 551 (97) | Signs/Symptoms, Major | 30.7 |
| VADG 32 | 1,347 (206) | Malignancy | 11.1 |
NOTES: JHU is Johns Hopkins University. ADG is ambulatory diagnosis group morbidity classification method of the Ambulatory Care Group case-mix system. MDCs are major diagnostic categories (clusters of diagnosis-related groups). VADGs are “visit” ambulatory diagnostic group categories (of ACG system) derived from all available diagnoses on face-to face ambulatory visit claims. (See Table 1 for examples of ICD-9-CMs grouped into each ADG.) Independent variables are derived from 1991 claims data of a sample of approximately 620,000 Medicare beneficiaries. SEs are standard errors of the coefficients. Population is the percent of patients flagged by each model variable. As the MDCs are count variables, their percentages reflect the percent of patients who had one or more admissions per MDC. However, of those patients hospitalized in 1991 within an MDC, an average of 92 percent were admitted only once in that MDC. The dependent variable is 1992 Medicare total expenditures.
SOURCE: Analyses on 1991-92 project data by authors during 1994-95.