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Data availability scenarios for hypothetical two-phase studies of the Ohio lung cancer mortality example
| Design | Elements available at phase I | Number of phase I strata | Elements requiring collection at phase II |
|---|---|---|---|
| 1a | Y, Age, Sex, Race | 24 | NA |
| 2b | Y | 2 | Age, Sex, Race |
| 3 | Y, Age | 6 | Sex, Race |
| 4 | Y, Sex | 4 | Age, Race |
| 5 | Y, Race | 4 | Age, Sex |
| 6 | Y, Age, Sex | 12 | Race |
| 7 | Y, Age, Race | 12 | Sex |
| 8 | Y, Sex, Race | 8 | Age |
equivalent to a complete data design
equivalent to a case-control design
