Cohort characteristics (n=946)
| Characteristic | Freq. | (%) |
| Age | 14 | 2.99 |
| Gender (% male) | 413 | (44%) |
| Median income | ||
| Low | 0 | (0%) |
| Lower-middle | 81 | (9%) |
| Upper-middle | 707 | (75%) |
| Upper | 158 | (17%) |
| Race (n=916) | ||
| White | 794 | (87%) |
| Black American | 21 | (2%) |
| Asian | 33 | (4%) |
| Native Hawaiian or Pacific Islander | 2 | (0%) |
| American Indian or Alaskan Native | 5 | (1%) |
| Multiracial | 61 | (7%) |
| Sport-specialised athletes | 759 | (80%) |
| Reported legal PES use | 136 | (14%) |
| Consideration of banned PES use | 28 | (3%) |
PES, performance-enhancing substance.