Table 1.
Demographic Characteristics of Research Participants.
| All participants (n = 196) | Participants in ASI (n =33) | Participants in PET scan and ASI (n = 20) | ||||||
|---|---|---|---|---|---|---|---|---|
| Control group (n = 102) | MA group (n = 94) | Group difference: p-value | Control group (n = 20) | MA group (n = 27) | Group difference: p-value | MA group | MA group | |
| Age (years) | 33.7 ± 8.94 | 34.2 ± 9.70 | 0.751 a | 36.3 ± 7.09 | 31.5 ± 8.65 | 0.048 a | 33.2 ± 9.62 | 30.0 ± 8.10 |
| Sex (Male/ Female) | 48 / 54 | 56 / 38 | 0.079 b | 10 / 10 | 14 / 13 | 0.900 b | 20 / 13 | 11 / 9 |
| Ethnicity | 45 Caucasian, 31 Hispanic, 13 African American, 5 Asian, 8 other | 45 Caucasian, 28 Hispanic, 7 African American, 3 Asian, 11 other | 0.264 b | 12 Caucasian, 3 Hispanic, 1 African American, 2 Asian, 2 other | 16 Caucasian, 7 Hispanic, 2 Asian, 2 other | 0.604 b | 15 Caucasian, 11 Hispanic, 2 Asian, 5 other | 9 Caucasian, 7 Hispanic, 2 Asian, 2 other |
| Education (years) | 12.9 ± 1.91 | 12.1 ± 1.67 | 0.001 a | 13.9 ± 2.03 | 12.3 ± 1.69 | 0.005 a | 12.1 ± 2.12 | 11.7 ± 2.17 |
| Tobacco Smokers | 32 | 76 | < 0.001 b | 11 | 23 | 0.045 b | 29 | 17 |
| Regular marijuana userc | 12 | 41 | < 0.001 b | 0 | 12 | < 0.001 b | 15 | 10 |
| Self-report of methamphetamine use | ||||||||
| Days abstinent before administration of DERS | - | 4.5 ± 3.37 | - | 4.0 ± 2.59 | 4.6 ± 3.62 | 4.1 ± 2.69 | ||
| Days abstinent before administration of PET scan | - | - | 6.9 ± 2.24 | 7.0 ± 2.45 | ||||
| Days of use in month before testing | - | 21.2 ± 8.46 | - | 21.3 ± 8.06 | 21.9 ± 7.73 | 22.7 ± 7.39 | ||
| Age of first use (years) | - | 21.0 ± 6.77 | - | 21.4 ± 6.97 | 19.0 ± 5.50 | 19.5 ± 5.00 | ||
a
Group difference evaluated by Student’s t-test.
b
Group difference in likelihood evaluated by Pearson’s Chi-square test.
c
Used marijuana within 1 month of enrolling in the study.
Data is shown as mean ± SD.
MA: methamphetamine.