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Rates of recruitment by source.
| Parameter | Recruitment source | ||||
|
|
Traditional (n=298) |
Free internet (n=382) |
Facebook ad (n=1299) |
Google ad (n=101) |
Survey panel (n=548) |
| Duration of use (months) | 18 months | 18 months | 14 months | 2 months | 5 months |
| Recruitment rate (persons per month) | 16.56 | 21.22 | 92.79 | 50.50 | 109.60 |
