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Evidence levels for in-text citations for empirical claims
| Evidence level | Type of work |
|---|---|
| 1 | Quantitative meta-analysis |
| 2 | Narrative review |
| 3 | Multiple original experiments/randomized controlled trials (RCTs) |
| 4 | Single original experiment/RCT |
| 5 | Correlational or quasi-experimental study |
| 6 | Opinion paper |
