Table 2. Findings on Univariate Meta-Regression of Factors Associated With Between-Study Variation in RCTs of Psychological Treatments in Prisons.
| Variable | β | SE (β) | p |
|---|---|---|---|
| * p < .05. ** p < .01. | |||
| Gender | .27 | .18 | .15 |
| Mean age (continuous) | .01 | .01 | .45 |
| Age group (adult vs. adolescent) | −.09 | .30 | .77 |
| Year of study (continuous) | −.01 | .01 | .38 |
| Country (USA vs. rest of the world) | −.25 | .19 | .20 |
| Retention rate | |||
| Continuous | −1.55 | .62 | .02* |
| Low (≤80%) vs. high (>80%) | −.41 | .18 | .03* |
| Sample size | |||
| Continuous | −.002 | .001 | .16 |
| ≤100 vs. >100 | −.33 | .18 | .08 |
| Diagnosis (required vs. not required) | −.16 | .18 | .37 |
| Study quality (high vs. medium) | −.34 | .22 | .13 |
| Fidelity measure | −.34 | .23 | .15 |
| Treatment length | .01 | .02 | .38 |
| Control group (no TR/waitlist vs. TAU/other therapy) | −.52 | .16 | <.01** |