Table 1.
Demographic characteristics and drug use measures by study group
| Test (χ2, F, t, or Z) | HC (n = 28) | iCUD (n = 30) | |
| Demographics | |||
| Age (years) | −1.19 | 42.04 ± 7.85 | 44.49 ± 7.88 |
| Gender (male/female) | 1.72 | 17/11 | 23/7 |
| Race (African American/Caucasian/Hispanic/Other) | 4.00 | 19/2/5/2 | 24/3/3/0 |
| Education (years) | 1.12 | 14.29 ± 2.09 | 12.77 ± 1.74 |
| Nonverbal IQ: Wechsler Abbreviated Scale of Intelligence Matrix Reasoning Scale scaled score | 0.81 | 10.75 ± 2.73 | 10.13 ± 3.07 |
| Depression: Beck Depression Inventory II* | 1.38 | 2.43 ± 3.69 | 7.33 ± 8.01 |
| Drug Use | |||
| Cigarette smokers (current/past or nonsmoker)* | 28.73 | 4/24 | 24/6 |
| Daily cigarettes in current smokers | −2.02 | 2.16 ± 3.93 | 7.23 ± 5.80 |
| Age of onset of cocaine use (years) | — | — | 20.63 ± 5.07 |
| Duration of use of cocaine (years) | — | — | 16.57 ± 8.27 |
| Duration of current abstinence (days) | — | — | 264.34 ± 541.42 |
| Frequency of cocaine use (last 30 d): days/week | — | — | 6.60 ± 9.00 |
| Cocaine Selective Severity Assessment (range: 0 to 126) | — | — | 14.73 ± 7.23 |
| Cocaine Craving Questionnaire (range: 0 to 45) | — | — | 16.33 ± 13.78 |
| Cocaine Severity of Dependence (range: 0 to 15) | — | — | 5.27 ± 4.73 |
*P < 0.05; χ2 tests were used for categorical variables; Mann–Whitney U test for all drug-related variables (continuous nonnormally distributed variables) and t tests for all between-group comparisons; values are frequencies or means ± SD.