| Characteristics | Groups˚ | Total |
| Sex―n (%) | Female | 13 (59.1) |
| ˚ | Male | 9 (40.9) |
| Age―mean (SD) |
| 43.0 (12.2) |
| Race―n (%) | White | 12 (63.2) |
| ˚ | Nonwhite | 8 (36.8) |
| Study years―n (%) | <9 | 8 (50.0) |
|
| 9 - 11 | 2 (12.5) |
|
| ≥12 | 6 (37.5) |