Table 6. Difference between last-resort and other hospitals in share of hospital Medicare caseload made up of patients in unprofitable diagnosis-related groups (DRGs): United States, 1984 and 1985.
| Year and variable | Coefficient | t |
|---|---|---|
| 1984, PPS year 11 | ||
| Intercept | 0.0023 | 5.45 |
| Difference in shares in 1981 | 0.74 | 5.25 |
| Variable = 1 if 1984 profits < 0; otherwise = 0 | 0.0014 | 3.31 |
| Variance of profit in 1984 | −4.1×10−11 | −0.44 |
| 1985, PPS year 22 | ||
| Intercept | 0.0024 | 9.16 |
| Difference in shares in 1981 | 0.68 | 5.02 |
| Variable = 1 if 1984 profits < 0; otherwise = 0 | 0.0013 | 4.02 |
| Variance of profit in 1984 | −4.1×10−11 | −2.05 |
The estimated equation is based on 35 DRGs with 100 cases or more in last-resort hospitals in PPS year 1. Observations are weighted by [(N84LR) (N84NLR)]/[(N84LR) (p(NLR)) (1 − p(NLR)) + (N84NLR) (p(LR)) (1 − p(LR))], where N84LR is the number of cases in PPS year 1 in last-resort hospitals, N84NLR is the number of cases in PPS year 1 in other hospitals, p(LR) is the share of cases in last-resort hospitals, and p(NLR) is the share of cases in other hospitals.
The regression is based on 33 DRGs with 100 cases or more in last-resort hospitals in PPS year 2. The weight is based on an analogous formula to that used for PPS year 1, outlined in footnote 1.
NOTES: Dependent variable is share of total cases in DRG(i) in last-resort hospitals – share of total cases in DRG(i) in other hospitals during the year. Only DRGs with 100 cases or more in last-resort hospitals during the year are included. PPS year 1 is the first year of implementation of the prospective payment system at the hospital level. For a hospital whose fiscal year begins on Oct. 1, 1983, it is Oct. 1, 1983, through Sept. 30, 1984. For a hospital whose fiscal year begins on July 1, 1984, it is July 1, 1984, through June 30, 1985. PPS year 2 is the second year after implementation (defined similarly). Last-resort hospitals are generally city and county hospitals in cities of 1 million population or more; the remainder of the hospitals in these cities are designated “other.” Data from waiver States are excluded. Figures are based on a 5-percent sample of cases.
SOURCE: Health Care Financing Administration, Bureau of Data Management and Strategy: Data from the Medicare Provider Analysis and Review (MEDPAR) file and Medicare cost reports.