Results of the Q18 in different groups
| Q18 results | Psycho-organic syndrome |
Lung disease | Exposed to solvents | Controls | Men | Women |
| n | 25 | 25 | 483 | 193 | 238 | 202 |
| Mean | 11.8 | 3.9 | 2.9 | 2.5 | 2.3 | 3.2 |
| Median | 14 | 3 | 2 | 1 | 2 | 3 |
| Range | 5–18 | 0–11 | 0–18 | 0–18 | 0–13 | 0–15 |
| ⩾5 (%) | 100 | 32 | 26 | 17 | 16 | 26 |
| ⩾6 (%) | 84 | 24 | 18 | 11 | 10 | 18 |
| ⩾7 (%) | 76 | 24 | 13 | 9 | 7 | 11 |
.