Efficacy of a Digital Nonattachment-Based Intervention for Post-traumatic Stress Symptoms: A Randomised Controlled Trial

Abstract Objectives Nonattachment, defined as the capacity to relate to internal experiences, identities, and external circumstances without clinging, avoidance, or over-identification, has been associated with reduced psychological distress and enhanced well-being, yet its deliberate cultivation within trauma-focused interventions remains underexplored. This study evaluated Nonattachment for Post-Traumatic Stress (NPTS), a co-created, self-guided digital intervention designed to cultivate nonattachment as a therapeutic process for individuals experiencing post-traumatic stress symptoms. Method A two-arm, parallel-group randomised controlled trial ( n = 141) compared NPTS with a waitlist control. Participants meeting DSM-5 or ICD-11 criteria for post-traumatic stress disorder (PTSD) were randomised to either NPTS or a waitlist control. NPTS is an eight-module, self-guided digital programme incorporating psychoeducation, guided contemplative and somatic practices, and structured reflection exercises designed to cultivate nonattachment. Outcomes were assessed at baseline, 8 weeks, and 20 weeks using the PTSD Checklist for DSM-5, Nonattachment Scale, Acceptance and Action Questionnaire-II, and Five Facet Mindfulness Questionnaire. Analyses followed CONSORT (2025) guidance and included intention-to-treat analyses using last observation carried forward, complete-case sensitivity analyses, and exploratory mediation analyses examining nonattachment and psychological flexibility. Results Compared with waitlist participants, intervention participants showed significantly greater reductions in PTSD symptoms at 8 weeks and 20 weeks, with large between-group effect sizes in intention-to-treat analyses. Participants in the intervention group also demonstrated increases in nonattachment and reductions in psychological inflexibility. Exploratory mediation analyses suggested that changes in nonattachment and psychological flexibility were associated with PTSD symptom reduction. Conclusions Findings provide evidence for the feasibility and potential efficacy of a co-created, nonattachment-based digital intervention for post-traumatic stress and support further investigation of nonattachment as a cultivable process within trauma-informed, second-generation mindfulness-based interventions. Preregistration This trial was pre-registered at Clinicaltrials.gov: NCT06683027.