Table 1. Description of regression variables.
| Variable | Description |
|---|---|
| Description and payment | |
| IRB | 1 plus the ratio of residents to beds |
| CMI | 1984 Medicare case-mix index (1981 case-mix index if 1981 cost data used) |
| WI | Medicare wage index |
| URBAN | 1 if located in a metropolitan statistical area (MSA) |
| MPOP2 | 1 if located in an MSA with between 250,000 and 1 million in population |
| MPOP3 | 1 if located in an MSA with more than 1 million in population |
| CC | Central city within MPOP3 |
| URB | Located in a rural county that contains a city or town of at least 20,000 in population |
| LOWIN | The sum of the percent of Medicare days attributable to Supplemental Security Income recipients and the percent of total days for which Medicaid is principal payer |
| URB>99 | 1 if urban hospital with more than 99 beds |
| DSHVARS | Five variables restricted to produce the exact payment adjustment for each hospital specified under the current disproportionate-share adjustment |
| BEDS | Number of beds |
| Bed deciles—Urban hospitals | |
| BED2 | Number of beds greater than or equal to 54 and less than 90 |
| BED3 | Number of beds greater than or equal to 90 and less than 121 |
| BED4 | Number of beds greater than or equal to 121 and less than 159 |
| BED5 | Number of beds greater than or equal to 159 and less than 204 |
| BED6 | Number of beds greater than or equal to 204 and less than 251 |
| BED7 | Number of beds greater than or equal to 251 and less than 310 |
| BED8 | Number of beds greater than or equal to 310 and less than 387 |
| BED9 | Number of beds greater than or equal to 387 and less than 506 |
| BED10 | Number of beds greater than or equal to 506 |
| Bed deciles—Rural hospitals | |
| RBED2 | Number of beds greater than or equal to 24 and less than 30 |
| RBED3 | Number of beds greater than or equal to 30 and less than 37 |
| RBED4 | Number of beds greater than or equal to 37 and less than 45 |
| RBED5 | Number of beds greater than or equal to 45 and less than 53 |
| RBED6 | Number of beds greater than or equal to 53 and less than 66 |
| RBED7 | Number of beds greater than or equal to 66 and less than 85 |
| RBED8 | Number of beds greater than or equal to 85 and less than 110 |
| RBED9 | Number of beds greater than or equal to 110 and less than 159 |
| RBED10 | Number of beds greater than or equal to 159 |
| Dependent | |
| MOCC | Medicare cost per discharge, net of capital and direct medical education expenditures, hospital years beginning in fiscal year 1984 |
| STDCST | MOCC standardized by CMI and WI |
| STDCSTO | STDCST net of estimated outlier payments per discharge |
| FSTD | MOCC standardized for CMI, WI, indirect-teaching and disproportionate-share payments |
| FSTDO | FSTD net of estimated outlier payments per discharge |
NOTE: All continuous variables except LOWIN are measured in natural logarithms.
SOURCE: Sheingold, S.: Battelle Institute, Washington, D.C., 1990.