Table 2.
Demographic and Baseline Characteristics
| Pilots | Randomized Patients | ||||
|---|---|---|---|---|---|
|
| |||||
| Variable | Contingency management | Standard care | Contingency management | Statistical test value (df) | p |
| N | 51 | 59 | 71 | ||
| Clinic | χ2(2)=3.99 | .14 | |||
| Clinic A | 31.4 (16) | 42.4 (25) | 28.2 (20) | ||
| Clinic B | 29.4 (15) | 20.3 (12) | 33.8 (24) | ||
| Clinic C | 39.2 (20) | 37.3 (22) | 38.0 (27) | ||
| Age | 39.7 ± 7.2 | 36.4 ± 9.6 | 37.0 ± 9.2 | t (128) = 0.31 | .76 |
| Male, % (n) | 52.9 (27) | 57.6 (34) | 49.3 (35) | χ2 (1) = 0.90 | .34 |
| Years of education | 12.0 ± 1.3 | 11.7 ± 2.1 | 11.3 ± 1.6 | t (128) = −1.41 | .16 |
| Currently married, % (n) | 25.5 (13) | 13.6 (8) | 14.1 (10) | χ2(1) = 0.01 | .93 |
| Employed full-time, % (n) | 49.0 (25) | 54.2 (32) | 52.1 (37) | χ2 (1) = 0.06 | .81 |
| Past month income | $1481 ± $1429 | $717 ± 1,006 | $875 ± 1210 | t (235) = 1.29 | .20 |
| Ethnicity, % (n) | χ2 (3) = 4.30 | .23 | |||
| African American | 9.8 (5) | 10.2 (6) | 5.6 (4) | ||
| European American | 64.5 (33) | 62.7 (37) | 78.9 (56) | ||
| Hispanic American | 21.6 (11) | 23.7 (14) | 12.7 (9) | ||
| Other | 3.9 (2) | 3.4 (2) | 2.8 (2) | ||
| Alcohol dependent, % (n) | not assessed | 13.6 (8) | 14.1 (10) | χ2 (1) = 0.01 | .93 |
| Methadone dose (mg) | 84.9 ± 24.3 | 91.1 ± 29.0 | 87.2 ± 25.4 | t (125) = −0.82 | .41 |
| Intake sample cocaine and alcohol negative, % (n) | not assessed | 45.8 (27) | 52.1 (37) | χ2 (1) = 0.52 | .47 |
| Addiction Severity Index Scores | |||||
| Medical | not assessed | 0.31 ± 0.38 | 0.34 ± 0.38 | t (128) = 0.54 | .60 |
| Employment | not assessed | 0.57 ± 0.55 | 0.55 ± 0.27 | t (128) = −0.36 | .72 |
| Alcohol | not assessed | 0.05 ± 0.11 | 0.04 ± 0.10 | t (128) = −0.16 | .87 |
| Drug | not assessed | 0.19 ± 0.09 | 0.17 ± 0.08 | t (128) = −1.69 | .09 |
| Legal | not assessed | 0.10 ± 0.21 | 0.06 ± 0.13 | t (128) = −1.23 | .22 |
| Family/social | not assessed | 0.17 ± 0.20 | 0.20 ± 0.24 | t (128) = 0.96 | .34 |
| Psychiatric | not assessed | 0.30 ± 0.24 | 0.27 ± 0.20 | t (128) = −0.72 | .48 |
Note. Values are means and standard deviations unless otherwise noted. Statistical analyses refer to comparisons between patients randomized to the two treatment conditions.