Main categories
| Main class | Number of findings by 1-16-2020 |
| AGE groups | 1900 |
| CHILDREN special | 5 |
| CONVINCTIONS | 3 |
| COMMUNAL LIVING | 6 |
| DEVIANT | 0 |
| ETHNIC GROUP | 51 |
| EDUCATION | 436 |
| EMPLOYMENT | 206 |
| FAMILY | 45 |
| GENDER | 165 |
| HEALTH | 168 |
| INCOME | 17 |
| INSTITUTIONAL LIVING | 25 |
| INTELLIGENCE | 6 |
| LIFE-HISTORY | 8 |
| LIFE-STYLE | 33 |
| LIFE-STRESS | 55 |
| LOVE-LIFE | 1 |
| MARITAL STATUS | 64 |
| MIGRATION | 44 |
| MEMBERSHIPS | 8 |
| OCCUPATION | 127 |
| PERSONALITY | 10 |
| PARENTHOOD | 106 |
| POSSESSIONS | 2 |
| PRACTICES | 0 |
| PRISONERS | 2 |
| PROSTITUTES | 3 |
| RELIGION | 4 |
| RESIDENCE | 155 |
| SOCIAL STATUS | 20 |
| SPORTS | 3 |
| THERAPY | 52 |
| WELL-BEING | 2 |
Example of a sub–classification
| Sub class | Number of findings by 1-6-2020 |
EDUCATION | |
| High school pupils | 78 |
| University students | 339 |
| Trainees | 4 |
| Alumni | 5 |
| School-leavers | 3 |
| Highly educated | 6 |
We speak of a ‘special public’ if this is the population studied and this kind of people was sampled for that purpose. This classification does not cover subgroups distinguished in wider populations.
The numbers in the right hand columns refer to studies that were entered in the finding archive. To date (2020) a lot of studies are still on the waiting list.