Table 2.
Pretest-adjusted mean effect sizes, 95% confidence intervals, and heterogeneity statistics by brief intervention target, outcome domain, and effect size type.
| Drug-targeted interventions | Alcohol-targeted interventions | |||||||
|---|---|---|---|---|---|---|---|---|
| Outcome domain Effect size type | [95% CI] | [95% PI] | τ 2 | I2 (%) | [95% CI] | τ2 [95% PI] | τ 2 | I2 (%) |
| Alcohol use | ||||||||
| SMD | 0.08 [−0.0003, 0.17]12, 71 | [−0.09, 0.26] | 0.00 | 27.17 | 0.12 [0.08, 0.16] 60, 396 | [−0.12, 0.37] | 0.01 | 51.21 |
| RR | 1.01 [0.92, 1.11]8, 39 | [0.93, 1.10] | 0.00 | 0.00 | 1.11 [1.04, 1.19] 27, 105 | [1.05, 1.19] | 0.00 | 0.00 |
| Cannabis use | ||||||||
| SMD | 0.06 [0.001, 0.12]13, 53 | [0.004, 0.11] | 0.00 | 0.00 | — | — | — | |
| RR | — | — | — | — | — | — | ||
| Multiple drug/mixed substance use | ||||||||
| SMD | 0.08 [0.002, 0.15] 16, 93 | [−0.10, 0.25] | 0.01 | 27.28 | — | — | — | |
| RR | — | — | — | — | — | — | ||
| Consequences | ||||||||
| SMD | 0.05 [0.01, 0.10]12, 80 | [−0.21, 0.31] | 0.01 | 48.33 | 0.05 [−0.04, 0.13]15, 64 | [−0.10, 0.19] | 0.00 | 18.41 |
| RR | — | — | — | 1.06 [0.94, 1.18]8, 38 | [0.95, 1.17] | 0.00 | 0.00 | |
Notes. Results in boldface are significantly different from null value (i.e., indicating no difference between intervention and comparison conditions) after Benjamini-Hochberg adjustment for multiple comparisons. = average effect size. CI = 95% confidence interval with robust standard errors. PI = 95% prediction interval. SMD = bias-adjusted standardized mean difference (Hedges’ g). RR = risk ratio.
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indicates results not available due to inadequate effect sizes and/or degrees of freedom. Subscripts indicate k (number of studies), n (number of effect sizes).