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Number of participants in each year of the study (and the percentage of participants retained, compared to the first year of the study): by region and grade level at recruitment
| Year | Region | Grade level at recruitment | |
|---|---|---|---|
| Grade 7 | Grade 11 | ||
| 2008 | Metropolitan | 366 | 155 |
| Non-metropolitan | 123 | 88 | |
| 2009 | Metropolitan | 310 (85 %) | 123 (79 %) |
| Non-metropolitan | 99 (80 %) | 73 (83 %) | |
| 2010 | Metropolitan | 253 (69 %) | 70 (45 %) |
| Non-metropolitan | 81 (66 %) | 44 (50 %) | |
