for the main comparison.
| Trauma‐focused psychological therapy compared to control intervention | ||||||
| Patient or population: Individuals with post‐traumatic stress disorder and comorbid substance use disorder Settings: Community addiction and mental health services Intervention: Individual‐based psychological therapy including a trauma‐focused component Comparison: Treatment as usual/minimal intervention/placebo intervention | ||||||
| Outcomes | Illustrative comparative risks* (95% CI) | Relative effect (95% CI) | No of Participants (studies) | Quality of the evidence (GRADE) | Comments | |
| Assumed risk | Corresponding risk | |||||
| TAU/ minimal intervention | Individual‐based psychological therapyincluding a trauma‐focused component | |||||
|
PTSD severity following treatment completion As assessed by the CAPS, PSS‐I, or IES‐R. High scores indicate greater symptom severity |
‐ | The mean PTSD severity following treatment completion in the intervention groups was 0.41 standard deviations lower (0.72 to 0.1 lower) | ‐ | 405 (4 studies) | ⊕⊝⊝⊝ very low1,2,3 | SMD ‐0.41 (‐0.72 to ‐0.1) Effect sizes of the range 0.2 to 0.5 indicate a small treatment effect |
|
Drug or alcohol use, or both following treatment completion As assessed by the TLFB or CIDI. High scores indicate greater symptom severity |
‐ | The mean drug/alcohol use following treatment completion in the intervention groups was 0.13 standard deviations lower (0.41 lower to 0.15 higher) | ‐ | 388 (3 studies) | ⊕⊝⊝⊝ very low1,2,3 | SMD ‐0.13 (‐0.41 to 0.15) Not significant |
| Treatment completers | Study population | RR 0.80 (0.69 to 0.93) | 316 (3 studies) | ⊕⊕⊝⊝ low1,3 | Indicates higher drop‐out in the intervention group | |
| 761 per 1000 | 609 per 1000 (525 to 708) | |||||
| Moderate | ||||||
| 718 per 1000 | 574 per 1000 (495 to 668) | |||||
| *The basis for the assumed risk (e.g. the median control group risk across studies) is provided in footnotes. The corresponding risk (and its 95% confidence interval) is based on the assumed risk in the comparison group and the relative effect of the intervention (and its 95% CI). CAPS: Clinician Administered PTSD Scale; CI: confidence interval; CIDI: Composite International Diagnostic Interview; IES‐R: Impact of Events Scale‐Revised; PSS‐I: PTSD Symptom Scale‐Interview; PTSD: post‐traumatic stress disorder; RR: risk ratio; SMD: standardised mean difference; TAU: treatment as usual; TLFB: Timeline Followback Interview | ||||||
| GRADE Working Group grades of evidence High quality: Further research is very unlikely to change our confidence in the estimate of effect. Moderate quality: Further research is likely to have an important impact on our confidence in the estimate of effect and may change the estimate. Low quality: Further research is very likely to have an important impact on our confidence in the estimate of effect and is likely to change the estimate. Very low quality: We are very uncertain about the estimate. | ||||||
1Quality of evidence downgraded by one point because the risk of bias in most trials was high or unclear in several domains. 2Quality of evidence downgraded by one point because of a high level of unexplained statistical heterogeneity. 3Quality of evidence downgraded by one point as a result of significant clinical heterogeneity.
SUD based adjunctive therapy was not a formal part of either the experimental or control condition in one study (Coffey 2006). However, participants were recruited through an SUD based service and it is likely that they would have had access to adjunctive SUD‐ based therapy on an informal basis. All other studies in this comparison included formal access SUD‐based adjunctive therapy.