Testing the effectiveness and implementation of a brief version of the Common Elements Treatment Approach (CETA) in Ukraine: a study protocol for a randomized controlled trial

Background: Mental illness is a major public health concern. Despite progress understanding which treatments work, a significant treatment gap remains. An ongoing concern is treatment length. Modular, flexible, transdiagnostic approaches have been offered as one solution to scalability challenges. The Common Elements Treatment Approach (CETA) is one such approach and offers the ability to treat a wide range of common mental health problems. CETA is supported by two randomized trials from low-and middle-income countries showing strong effectiveness and implementation outcomes. Methods/design: This trial evaluates the effectiveness and implementation of two versions of CETA using a non-inferiority design to test two primary hypotheses: (1) a brief five-session version of CETA (Brief CETA) will provide similar effectiveness for reducing the severity of common mental health problems such as depression, post-traumatic stress, impaired functioning, anxiety, and substance use problems compared with the standard 8-12-session version of CETA (Standard CETA); and (2) both Brief and Standard CETA will have superior impact on the outcomes compared to a wait-list control condition. For both hypotheses, the main effect will be assessed using longitudinal data and mixed-effects regression models over a 6-month period post baseline. A secondary aim includes exploration of implementation factors. Additional planned analyses will include exploration of: moderators of treatment impact by disorder severity and comorbidity; the impact of individual therapeutic components; and trends in symptom change between end of treatment and 6-month assessment for all participants. Discussion: This trial is the first rigorous study comparing a standard-length (8-12 sessions) modular, flexible, transdiagnostic, cognitive-behavioral approach to a shortened version of the approach (five sessions). Brief CETA entails front-loading with elements that research suggests are strong mechanisms of change. The study design will allow us to draw conclusions about the effects of both Brief and Standard CETA as well as which elements are integral to their mechanisms of action, informing future implementation and fidelity efforts. The results from this trial will inform future dissemination, implementation and scale-up of CETA in Ukraine and contribute to our understanding of the effects of modular, flexible, transdiagnostic approaches in similar contexts.