Evidence Grading
Not all evidence is equal. A simplified grading system helps readers understand the strength of claims:
| Grade | Meaning | Typical Sources |
|---|---|---|
| Strong | Consistent findings across multiple high-quality studies | Meta-analyses, multiple RCTs |
| Moderate | Promising findings, some limitations | Single RCT, multiple observational studies |
| Emerging | Initial evidence, needs replication | Pilot studies, case series |
| Limited | Insufficient data, theoretical basis only | Expert opinion, analogous research |
A note on effect sizes: Throughout this research, effect sizes (Cohen's d or Hedges' g) are reported where available. For context:
- d = 0.2 is "small" (visible to careful measurement)
- d = 0.5 is "medium" (visible to casual observation)
- d = 0.8 is "large" (obvious to anyone)
Most digital mental health interventions show small-to-medium effects in controlled trials. Real-world effectiveness is typically lower.