Table 1.
Demographic characteristics and the prevalence of DSM-IV mental disorders in the sample.
| Characteristic |
|||
| Sex (% female) | 52.1 | ||
| Race-ethnic group (%) | |||
| Non-Hispanic white | 71.5 | ||
| African American | 25.2 | ||
| Other groups | 3.2 | ||
| Monozygotic twin (%) | 49.5 | ||
| Years of education completed (mean, SD) | 14.3 (2.3) | ||
| Still in school (%) | 26.0 | ||
| Age in years (mean, SD) | |||
| Wave 1 | 13.6 (2.5) | ||
| Wave 2 | 26.0 (1.8) | ||
| Diagnoses | Females | Males | Full Sample |
| N = 260 | N = 239 | N = 499 | |
| N (%) | N (%) | N (%) | |
| Specific phobia | 31 (11.9) | 17 (7.1) | 48 (9.6) |
| Agoraphobia | 21 (8.1) | 11 (4.6) | 32 (6.4) |
| Panic disorder | 11 (4.2) | 11 (4.6) | 22 (4.4) |
| Post-traumatic stress disorder | 10 (3.8) | 4 (1.7) | 14 (2.8) |
| Social anxiety disorder | 23 (8.8) | 6 (6.7) | 39 (7.8) |
| Obsessive-compulsive disorder | 15 (5.8) | 15 (6.3) | 30 (6.0) |
| Generalized anxiety disorder | 13 (5.0) | 7 (2.9) | 20 (4.0) |
| Major depression | 22 (8.5) | 17 (7.1) | 39 (7.8) |
| Dysthymia | 0 (0.0) | 0 (0.0) | 0 (0.0) |
| Attention-deficit/hyperactivity disorder | 7 (2.7) | 11 (4.6) | 18 (3.6) |
| Alcohol abuse | 25 (9.6) | 48 (20.2) | 73 (14.7) |
| Alcohol dependence | 8 (3.1) | 20 (8.4) | 28 (5.6) |
| Cannabis abuse | 13 (5.0) | 27 (11.3) | 40 (8.0) |
| Cannabis dependence | 5 (1.9) | 12 (5.0) | 17 (3.4) |
| Nicotine dependence | 20 (8.1) | 27 (12.3) | 47 (10.1) |
| Antisocial personality disorder | 15 (5.8) | 48 (20.1) | 63 (12.6) |
| Hypomania | 5 (1.9) | 6 (2.5) | 11 (2.2) |
| Mania | 1 (0.4) | 1 (0.4) | 2 (0.4) |