| Label | Id | |
|---|---|---|
| research dissemination | PROC:AOD | |
| empirical study | PROC:AOD | |
| experiment | PROC:AOD | |
| experimental research | PROC:AOD | |
| experimental study | PROC:AOD | |
| research study | PROC:AOD | |
| trial study | PROC:AOD | |
| local survey | PROC:AOD | |
| national survey | PROC:AOD | |
| demographic study | PROC:AOD | |
| poll | PROC:AOD | |
| social survey | PROC:AOD | |
| state survey | PROC:AOD | |
| telephone survey | PROC:AOD | |
| study of one area, group, or program | PROC:AOD |