Table 1.
Demographics for participants recruited at the Denver and San Diego sites at Wave 1 and Wave 2.
| Wave 1 (n=1,192) | Wave 2 (n = 875) | ||||
|---|---|---|---|---|---|
| Denver (n=710) | San Diego (n=482) | Denver (n=459) | San Diego (n=416) | ||
| Probands/Siblings | 351/359 | 245/237 | 225/234 | 206/210 | |
| M Age (SD) | 17.1 (2.3) | 17.6 (2.1) | 23.5 (2.7) | 23.8 (2.6) | |
| % Male | 69.3% | 55.5% | 68.2% | 54.9% | |
| % Hispanic | 24.4% | 45.0% | 23.1% | 42.8% | |
| White (Non-Hispanic) | 53.0% | 33.6% | 55.8% | 36.1% | |
| Black/African-American | 8.5% | 10.0% | 7.2% | 9.6% | |
| American Indian | 1.8% | 0.8% | 1.1% | 1.0% | |
| Asian/Pacific Islander | 0.4% | 3.1% | 0.4% | 3.1% | |
| Multiracial | 14.5% | 6.4% | 14.4% | 6.2% | |
| Other (Non-Hispanic) | 0.8% | 2.3% | 0.9% | 2.4% | |
| % Ever Used Cannabis | 88.5% | 87.1% | 94.5% | 92.8% | |
| Age of Onset of Monthly Cannabis Use [Minimum, Maximum] | 13.2 (2.0) [9, 20] | 14.2 (1.8) [9, 22] | 13.9 (2.2) [9, 25] | 14.9 (2.2) [9, 26] | |
| Monthly Frequency of Past Six Month Cannabis Usea | 9.2 (10.8) | 7.3 (10.7) | 8.3 (11.7) | 7.8 (11.7) | |
| Lifetime Frequency of Cannabis Useb | 42.0 (25.5) | 39.1 (26.2) | 50.4 (20.6) | 48.3 (21.5) | |
| % Ever Used Alcohol | 92.3% | 94.8% | 99.3% | 99.5% | |
| Age of Onset of Monthly Alcohol Use [Minimum, Maximum] | 14.7 (2.2) [9, 22] | 14.9 (2.1) [9, 22] | 15.5 (2.5) [9, 23] | 15.7 (2.5) [9, 28] | |
| Monthly Frequency of Past Six Month Alcohol Usea | 3.7 (6.0) | 4.0 (5.5) | 5.2 (8.3) | 7.3 (8.3) | |
| Lifetime Frequency of Alcohol Useb | 33.7 (24.4) | 40.3 (23.4) | 53.6 (15.0) | 55.6 (13.3) | |
| IQ | 93.8 (15.2) | 93.8 (15.7) | NA | NA | |
Note:
a
At both waves/sites, the minimum and maximum of monthly frequency of past six-month use were 0 and 30 days, respectively.
b
At both waves/sites, the minimum and maximum for lifetime frequency were 0 and 60, respectively. NA = not available.