Table 1.
Studies of Favorable HMO Selection in Medicare
| Study | Data Years | Health Status Measures | Cross-sectional Analysis? | Immediate Postenrollment Period Only? | Data Pooled Across Plans? | HMO Enrollees Healthier? |
|---|---|---|---|---|---|---|
| Demonstration HMOs | ||||||
| Eggers 1980 | 1974–1976 | Pre-enrollment utilization | Yes | Yes | No (1 plan) | Yes |
| Eggers and Prihoda 1982 | 1976–1979 | Pre-enrollment utilization | Yes | Yes | No | Yes |
| Hornbrook, Bennett, and Greenlick 1992 | 1980–1982 | Pre-enrollment utilization | No | Yes | No (1 plan) | Yes |
| Garfinkel et al. 1986 | 1980–1982 | Self-reported health status: | Yes | Done both ways | No | |
| Self-perceived health | No | |||||
| Functional limitations | No | |||||
| Health conditions | Yes, at 1 of 3 plans | |||||
| Kasper et al. 1988 | 1979–1982 | Pre-enrollment utilization | Both cross-sectional and panel | Yes | No | Yes |
| Self-perceived health | Yes, at 1 of 2 plans | |||||
| Self-reported health status | ||||||
| Functional limitations | ||||||
| Mathematica/MCV Evaluation | 1980–1985 | Pre-enrollment utilization | Yes | Yes | Done both ways | Yes, in 14 of 17 plans |
| (Brown 1987, Brown 1988; Brown and Langwell 1988; Langwell and Hadley 1989; Rossiter et al. 1989) | Self-reported health status | Yes | No | Yes | Yes | |
| Self-perceived health IADLs | Yes | |||||
| Bed days | Yes | |||||
| Health conditions | Yes | |||||
| Sociodemographics: | Yes | No | Yes | |||
| Marital Status | Yes | |||||
| Income | No | |||||
| Education | No | |||||
| Race | No | |||||
| Mathematica/MCV Evaluation (cont) | Postenrollment mortality | Yes | No | Done both ways | Yes, in 12 of 17 plans | |
| GAO 1986 | 1984 | Postenrollment mortality | Yes | No | Done both ways | Yes |
| Riley, Rabey, and Kasper 1989 | 1980–1986 | Postenrollment mortality | No | No | No | Yes |
| TEFRA HMOs | ||||||
| Hill and Brown 1990 | 1986–1987 | Pre-enrollment utilization | Yes | Yes | Yes | Yes |
| Riley, Lubitz, and Rabey 1991 | 1987 | Postenrollment mortality | Yes | No | Yes | Yes |
| Lichtenstein et al. 1991 | 1988 | Self-reported health status: | Yes | Yes | No | Yes, in 19 of 23 plans |
| Functional status | ||||||
| Dowd et al. 1994 | 1988 | Sociodemographics: | Yes | No | Yes | |
| Income | Yes | |||||
| Marital status | Yes | |||||
| Self-reported health status: | ||||||
| Health conditions | No | |||||
| Dowd et al. 1996 | 1988 | Self-reported health status: | Yes | No | Yes | Yes |
| Health conditions | Yes | |||||
| Hill and Brown 1992 | 1990 | Self-reported health status: | Yes | No | Yes | |
| Self-perceived health | Yes | |||||
| Health conditions | Yes | |||||
| Bed days | Yes | |||||
| Price Waterhouse 1996 | 1992 | Predicted costs | Yes | No | Yes | No |
| Riley et al. 1996 | 1994 | Self-reported health status: | Yes | No | Yes | |
| Self-perceived health | Yes | |||||
| ADLs/IADLs | Yes | |||||
| Health conditions | No | |||||
| Predicted costs | Yes | |||||
| Call et al. 1999 | 1993–1994 | Pre-enrollment utilization | Yes | Yes | Yes | Yes |
| Maciejewski et al. 2001 | 1993–1994 | Postenrollment mortality | Yes | No | Yes | Yes |
| Present study | 1993–1996 | Self-reported health status: | No | No | Yes | |
| Self-perceived health | Yes | |||||
| ADLs/IADLs | No | |||||
| Health conditions | Yes, for 3 conditions | |||||
| Social limitations | No | |||||