Table 2.
Sociodemographic and behavioral characteristics of participants at randomization
| Participant characteristics | Control (IO) n=414 | Treatment (IPC) n=416 | p value |
|---|---|---|---|
| Age (years) | 0.44a | ||
| Mean (SD) | 29.45 (7.66) | 29.8 (7.51) | |
| Median | 28 | 28 | |
| Race | 0.21c | ||
| Black/not Hispanic | 205 (49.5%) | 187 (45%) | |
| Marital status | 0.83c | ||
| Single | 209 (50.5%) | 214 (51.4%) | |
| Education | 0.21* | ||
| Grades 1–11 | 125 (30.2%) | 105 (25.2%) | |
| Grade 12 or GED | 145 (35%) | 166 (39.9%) | |
| College 1+ yrs. | 141 (34.1%) | 144 (34.6%) | |
| Income | 0.43c | ||
| <$20,000 | 221 (53.4%) | 235 (56.5%) | |
| AUDIT score | 0.41a | ||
| Mean (SD) | 17.48 (10.01) | 17.81 (9.69) | |
| Median | 15.5 | 16 | |
| Average number of drinks per week past 90 days | 0.35a | ||
| Mean (SD) | 37.08 (58.96) | 35.59 (55.54) | |
| Median | 16.96 | 18.04 | |
| Number of binge episodes past 3 months | 0.06a | ||
| Mean (SD) | 29.09 (29.96) | 30.06 (28.71) | |
| Median | 19 | 22 | |
| Average number of drinks per drinking day past 90 days | 0.64a | ||
| Mean (SD) | 8.01 (8.62) | 7.96 (8.48) | |
| Median | 4.99 | 5.34 | |
| DSM-IV criteria alcohol problems | 0.86* | ||
| 303.90 alcohol dependence | 234 (56.5%) | 230 (55.3%) | |
| 305.00 alcohol abuse | 31 (7.5%) | 27 (6.5%) | |
| V71.09 no diagnosis | 91 (22%) | 83 (20%) | |
| History of treatment for alcohol-related problems | 280 (67.6%) | 291 (70%) | 0.82a |
| Drug use in past 12 months | 379 (91.5%) | 389 (93.5%) | 0.34* |
| Current smoker | 299 (72.2%) | 316 (76%) | 0.30* |
| Number of sexual partners in past 3 months | 0.36a | ||
| Mean (SD) | 12.42 (54.23) | 7.61 (36.31) | |
| Median | 2 | 2 | |
| Contraception use (past 3 months) | 0.88* | ||
| Used contraception, but ineffectivelyb | 276 (66.7%) | 281 (67.5%) | |
| Used no contraception | 136 (32.9%) | 134 (32.2%) |
a
p values for differences in means across treatment groups were calculated using the Satterthwaite t-test for log-transformed data.
b
Includes consistent use of contraception method as prescribed by manufacturer.
c
p values are based upon the collapsed two-level covariate.
*
Differences in proportion across treatment groups were tested using the Fisher Exact Test (2-tailed) P-values less than .05 indicated statistically significant difference.
AUDIT, Alcohol Use Disorder Identification Test; DSM-IV, Diagnostic and Statistical Manual of Mental Disorders, Fourth Edition; GED, general equivalency diploma; IO, information only; IPC, information plus counseling.