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Criteria used to define overall study findings based on the associations measured
| Overall study findings | Statistical significance reported | Direction reported |
| Null | 0%−33% statistically significant associations | Inverse or expected |
| Mixed | 34%–59% statistically significant associations | Inverse or expected |
| Expected | More than 60% statistically significant associations | Expected |
| Inverse | More than 60% statistically significant associations | Inverse |
