| particularly | 28 | degree |
| in treating sleep disorders | 16 | other |
| in decreasing the amount of time | 15 | other |
| melatonin → be → effective | 176 |
| melatonin → be → more effective | 11 |
| melatonin → be → most effective | 10 |
| melatonin → be shown to be → effective | 4 |
| melatonin → be found → effective | 4 |
| melatonin → be → efficient | 3 |
| negative | neutral | positive |
| 0.043 | 0.298 | 0.659 |
| Raw frequency | 208 |
| Normalized frequency | 0.738 |
| Modifier score | 0.700 |
| Perplexity | 58.814 |