| Variable name | Description | Possible values | Missing (%) |
| The imputed variables | |||
| PRACSIZE2 | Practice size grouped into 2 groups | 1, 2 | 3.62 |
| PRACSIZE5 | Practice size grouped into 5 groups | 1, 2, 3, 4, 5 | 3.62 |
| PRACSIZE20 | Practice size top-coded to20 | 1 to 20 | 3.62 |
| PRACSIZE100 | Practice size: The number of physicians at the reporting location | 1 to 100 | 3.62 |
| CLSTAFF1 | Number of clinical staff | 0 to 99 | 8.88 |
| The independent variable used in hot-deck imputation | |||
| REGION | Region of the physician’s interview office | 1, 2, 3, 4 | 0 |
| SPECR | Physician specialty | 1, 3, 4, 5, ∙∙∙ , 15 | 0 |
| PRIMEMP | Primary present employment code | 11, 13, 20, 21, 22, 23, 30, 31 | 0 |