Severe posttraumatic stress disorder (PTSD) symptoms and the emergence of a complex posttraumatic stress disorder diagnosis (CPTSD), has contributed to clinical practice that is different in format than what is recommended by treatment guidelines for PTSD in adults. Phase-orientated approaches are commonly used with this population with the aim of stabilising trauma symptoms prior to engaging with exposure based trauma-focused treatment.

This review aimed to synthesise data on standalone stabilisation interventions and stabilisation followed by trauma-focused therapy (i.e. phase-orientated approach), to provide some clarity on the efficacy of these interventions.

A systematic search of the qualitative and quantitative literature found 6,400 articles, of which 31 met predefined criteria. A narrative synthesis approach was used to collate qualitative data. To analyse effect sizes in quantitative studies, a random effects meta-analysis was conducted.

The primary finding from the qualitative studies indicated that group stabilisation interventions are helpful for reducing trauma symptoms and in preparing for trauma-focused therapy. The themes supporting this finding were Group Process, Specific Skills and Psychoeducation, and Motivation and Readiness for Change. A secondary qualitative finding related to the challenges associated with implementing a stabilisation intervention. The themes giving rise to this finding are Stabilisation; A Demanding Process and the Structure of Stabilisation Interventions. A meta-analysis showed a medium effect size for PTSD symptom reduction using stabilisation interventions (d = 0.59 with 95% confidence intervals [CI] ranging from 0.14 to 1.04 (z = 2.58; p < .05). This effect size was reduced to a small effect when utilizing only randomised controlled trial (RCT) stabilisation data (d = .42, CI = 0.23 to 0.61, z = 4.37; p > .001).

There were no qualitative studies on phase-orientated treatment approaches found using review search criteria. A large effect size was found for phase-orientated quantitative studies (d = 1.32, CI = 0.88 to 1.76, z = 5.89; p < .001) and this large effect size was maintained using RCT data (d = 1.47, CI = 1.00 to 1.95, z = 6.05; p < 001). There was tentative evidence that phase-orientated treatment is more effective than standalone stabilisation, with a small effect size (d = .45, CI = 0.17 to 0.72, z = 3.19; p < .01).

The results of this review are consistent with previous literature supporting the effectiveness of stabilisation and phase-orientated models for reducing PTSD symptoms. Limitations pertaining to the heterogeneity of included studies and the difficulty in identifying which specific psychological models should be utilised in clinical practice as well as the generalisability of the findings to relevant populations are discussed.