| Levels | Coefficients(c) | Definitions |
| Very low | 1 | p < 10−6 |
| Once a year < p < 1 time per month | ||
| Low | 2 | 10−6 < p < 10−4 |
| 1 time per month < p < 1 time per week | ||
| Medium | 3 | 10−4 < p < 10−2 |
| 1 time per week < p < 1 time per day | ||
| Frequent | 4 | 10−3 < p < 10−1 |
| 1 time per day < p < 1 time per hour | ||
| Very frequent | 5 | 10−1 < p |
| p < 1 time per day |