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Number of studies identifying positive health impacts by study design type
| Study design | Number of Studies Included | Number of studies that found a positive health impact | Number of studies that found no, or negative, health impacts |
|---|---|---|---|
| Modeling | 17 | 16 | 3 |
| Experimental | 0 | 0 | 0 |
| Evaluation | 8 | 4 | 4 |
| Mixed methoda | 1 | 1 | 1 |
| Total | 26 | 21 | 9 |
aBoth modeling and evaluation
