Table 4.
Outcome scores at all 4 study points.
| Characteristics | Factor 1: Chat-based communicationa | Factor 2: Lengtha | ||||
|
|
No (n=263) | Yes (n=271) | 28 days (n=266) | 50 days (n=268) | ||
| Cannabis useb (days), mean (SD) |
|
|
|
|
||
|
|
Baseline | 24.7 (7.3) | 25.1 (6.5) | 24.9 (7.0) | 24.9 (6.8) | |
|
|
3 months | 8.1 (9.4) | 7.6 (9.6) | 8.6 (9.9) | 7.1 (9.1) | |
|
|
6 months | 8.5 (9.7) | 8.5 (9.9) | 9.4 (10.2) | 7.6 (9.3) | |
|
|
12 months | 9.6 (10.3) | 9.1 (10.3) | 10.3 (10.6) | 8.4 (9.9) | |
| Cannabis useb (number of events), mean (SD) |
|
|
|
|
||
|
|
Baseline | 122.5 (111.6) | 120.1 (104.1) | 123.7 (108.9) | 118.9 (106.8) | |
|
|
3 months | 25.2 (43.5) | 20.3 (35.7) | 25.3 (44.3) | 20.1 (35.0) | |
|
|
6 months | 29.1 (48.9) | 25.5 (45.0) | 30.4 (49.8) | 24.2 (44.1) | |
|
|
12 months | 33.9 (55.2) | 29.3 (51.1) | 35.2 (56.4) | 27.9 (49.5) | |
| Cannabis useb (grams), mean (SD) |
|
|
|
|
||
|
|
Baseline | 23.2 (18.8) | 21.3 (18.6) | 23.2 (19.6) | 21.3 (17.8) | |
|
|
3 months | 6.4 (9.8) | 5.0 (8.2) | 6.3 (9.7) | 5.2 (8.2) | |
|
|
6 months | 6.5 (9.5) | 5.5 (8.7) | 6.9 (10.1) | 5.1 (8.0) | |
|
|
12 months | 7.3 (10.6) | 6.8 (10.4) | 7.6 (10.8) | 6.5 (10.1) | |
| Cannabis dependence (SDSc), mean (SD) |
|
|
|
|
||
|
|
Baseline | 9.9 (2.8) | 10.0 (2.7) | 10.1 (2.5) | 9.8 (2.9) | |
|
|
3 months | 7.2 (3.5) | 6.8 (3.6) | 7.0 (3.5) | 6.9 (3.6) | |
|
|
6 months | 5.4 (3.5) | 5.1 (3.8) | 5.4 (3.6) | 5.1 (3.7) | |
|
|
12 months | 5.5 (3.6) | 5.4 (3.8) | 5.7 (3.6) | 5.2 (3.8) | |
| Working alliance (WAI-srd), mean (SD) |
|
|
|
|
||
|
|
3 months | 3.3 (1.0) | 3.5 (0.9) | 3.5 (0.9) | 3.3 (1.0) | |
| Treatment satisfaction (CSQ-8e), mean (SD) |
|
|
|
|
||
|
|
3 months | 1.8 (0.7) | 2.1 (0.7) | 2.0 (0.6) | 1.9 (0.7) | |
aIntention-to-treat analyses following multiple imputation. Results of the nonimputed datasets can be found in Multimedia Appendix 3.
bDuring the past 30 days.
cSDS: Severity of Dependence Scale.
dWAI-sr: Working Alliance Inventory-short revised.
eCSQ: Client Satisfaction Questionnaire.