Summary: A new study reveals that individuals living with co-occurring psychosis and Post-Traumatic Stress Disorder (PTSD) can safely and effectively achieve recovery through an integrated, trauma-focused therapy. The STAR (Study of Trauma And Recovery) study represents the largest multi-site randomized controlled trial of its kind to date.
Evaluating 305 participants across five UK sites over five years, the trial directly challenges a long-standing psychiatric taboo: that addressing severe trauma directly could exacerbate or destabilize active psychosis symptoms.
Key Facts
- The Treatment Success Rate: Following 9 months of integrated TF-CBTp, 50% of the treatment group no longer met clinical criteria for PTSD, compared to just over 20% who received treatment as usual.
- Overturning Historic Exclusion: People with psychosis have historically been systematically excluded from PTSD research due to clinician fears of worsening hallucinations or delusions. This study provides robust evidence that direct trauma memory processing is entirely safe.
- Remarkably High Engagement: The trial recorded an exceptionally low disengagement rate of just 6.5%, proving the tailored, flexible therapeutic framework is highly acceptable to a complex, heavily traumatized patient group.
- Broad-Spectrum Recovery: Participants experienced significant improvements across 22 out of 27 assessed clinical outcomes, showing a moderate-to-large reduction in PTSD severity alongside major reductions in depression, anxiety, suicidal ideation, paranoia, and multisensory hallucinations.
- A Scale-Up Initiative: The intervention is actively being scaled via the PICuP Clinic at SLaM, incorporating individuals with lived experience who went through the trial to co-deliver treatment training and combat internalized psychiatric stigma.
Source: King’s College London
New research from the Institute of Psychiatry, Psychology & Neuroscience (IoPPN) at King’s College London and published in The Lancet Psychiatry has found that people with psychosis experiencing Post Traumatic Stress Disorder (PTSD) can benefit from a Trauma-Focused therapy integrated with Cognitive Behaviour Therapy for psychosis (CBTp).
The STAR (Study of Trauma And Recovery) study, funded by the National Institute for Health and Care Research (NIHR) led by researchers at King’s IoPPN and South London and Maudsley NHS Foundation Trust (SLaM), recruited 305 participants and is the largest multi-site randomised controlled trial to date of a trauma-focused therapy for people with co-occurring diagnoses of psychosis and PTSD.
PTSD is characterised by intrusive trauma memories such as ‘flashbacks’ and other types of re-experiencing, negative appraisals, hyperarousal, and avoidance of trauma reminders. The prevalence of PTSD in people with psychosis is up to five times that in the general population, with PTSD symptoms often intertwined with psychosis symptoms such as delusions and hallucinations, and traumatic events often shaping their content.
In the past people with psychosis have been excluded from almost all PTSD research trials, and clinicians were wary of delivering Trauma-Focused therapy in routine clinics for fear of making the psychosis symptoms worse. But this study showed that an integrated Trauma-Focused-CBTp, lasting 9-months, was safe and highly effective with this group.
Half of the participants who received the therapy no longer met PTSD criteria post-therapy, compared to just over 20 per cent receiving treatment as usual, despite all participants reporting repeated and multiple traumas. A similar pattern was found for complex PTSD.
There were exceptionally low rates of disengagement from therapy (6.5 per cent), demonstrating the therapy is highly acceptable.
Professor Emmanuelle Peters, Professor of Clinical Psychology at King’s and the study’s first author said: “It is now clear that trauma-focused therapies can be delivered safely and effectively for people with PTSD and psychosis. Our results are robust in demonstrating that this intervention, which includes working on the trauma memory directly, a focus on engagement, and a flexible approach tailored to the individual, is safe, highly acceptable and effective on a range of PTSD, psychosis, and emotional well-being outcomes.”
Overall participants showed significant improvements in 22 out of 27 assessed outcomes. The primary outcome, PTSD symptom severity, demonstrated a moderate-to-large effect size, with additional effects ranging from large to small across psychosis symptoms (paranoia and multisensory hallucinations), mood disorders (depression, anxiety and suicidal ideation), and psychological recovery.
Dr Amy Hardy, Reader in Clinical Psychology at King’s and the joint-last author and joint-Therapy Lead for the study, said: “The results challenge a longstanding gap in mental healthcare, where people with psychosis have been excluded from trauma-focused therapies. Our findings demonstrate that this must change, to ensure those historically denied access can receive evidence-based care.”
Professor Peters leads a specialist psychological therapies team for outpatients with psychosis, the PICuP Clinic, based at SLaM. PICuP now provides Trauma-focused CBTp and training in the intervention to clinicians working with individuals with psychosis, led by the STAR Therapy Leads Dr Nadine Keen (PICuP Coordinator) and Dr Amy Hardy (PICuP and SLaM Psychology & Psychotherapy Trauma Informed Care for Psychosis Lead), alongside people with lived experience of trauma and psychosis who received the therapy in the trial.
One such participant, Shane now works as a Peer-Support Worker in PICuP and with Professor Peters on the Let’s Talk research trial at King’s and South London and Maudsley, delivering a peer-led programme to address internalised stigma for people with psychosis.
He said: “STAR therapy gave me the tools to make sense of experiences I had carried for years and change how I see myself and others. I didn’t just learn ways to manage and reshape trauma memories – I rebuilt trust, confidence, and a sense of connection. It gave me back a feeling of control and the belief that recovery is possible.”
Dr Nadine Keen, STAR joint-Therapy Lead, commented that “We hope the STAR trial will be a gamechanger for the psychological treatment of this highly complex and marginalised population, motivating commissioners and services to prioritise implementation of Trauma-Focused CBTp. This therapy can transform lives and underscores an ethical imperative: clinical services and research should not inadvertently perpetuate trauma survivors’ silence through exclusion.”
Funding: This research was possible thanks to funding by the National Institute for Health and Care Research (Health Technology Assessment). Over 120 people in five UK sites (London; Manchester; Newcastle; Oxford and Sussex) were involved in delivering the trial, which took five years to complete.
Key Questions Answered:
A: For decades, a pervasive fear existed within mental healthcare that directly confronting traumatic memories would destabilize patients with psychosis, making symptoms like delusions and hallucinations severely worse. Because of this, this vulnerable population was routinely locked out of clinical trials, effectively denying them access to frontline, evidence-based trauma care.
A: PTSD prevalence is up to five times higher in people with psychosis than in the general public. In these individuals, trauma memories and classic PTSD symptoms, such as flashbacks and hyperarousal, frequently become deeply intertwined with their psychosis. Crucially, their past real-world traumatic events often directly shape the terrifying themes and content of their active delusions and hallucinations.
A: The therapy combined Trauma-Focused techniques with Cognitive Behaviour Therapy for psychosis (CBTp) into a unified, 9-month program. Instead of avoiding the trauma, clinicians worked directly with the trauma memories. The framework succeeded because it utilized a highly flexible, individualized protocol focused heavily on building early patient engagement and trust, which kept the dropout rate at a tiny 6.5%.
Editorial Notes:
- This article was edited by a Neuroscience News editor.
- Journal paper reviewed in full.
- Additional context added by our staff.
About this PTSD and psychosis research news
Author: Franca Davenport
Source: King’s College London
Contact: Franca Davenport – King’s College London
Image: The image is credited to Neuroscience News
Original Research: Open access.
“Trauma-focused therapy integrated with cognitive behavioural therapy for psychosis for people with post-traumatic stress disorder and psychosis (the STAR trial) :a multicentre, pragmatic, randomised trial in the UK” by Peters, E., Swan, S., Underwood, R., Jafari, H., Varese, F., Steel, C., Dudley, R., Greenwood, K., Emsley, R., Keen, N., Bowe, S., Hardy, A., Morrison, A., and the STAR group. Lancet Psychiatry
DOI:10.1016/S2215-0366(26)00090-8
Abstract
Trauma-focused therapy integrated with cognitive behavioural therapy for psychosis for people with post-traumatic stress disorder and psychosis (the STAR trial): a multicentre, pragmatic, randomised trial in the UK
Background
People with psychosis have high rates of post-traumatic stress disorder (PTSD), which is associated with a poor prognosis. We aimed to investigate the effectiveness of a trauma-focused therapy integrated with cognitive behavioural therapy for psychosis (CBTp) in people with psychosis.
Methods
STAR was a rater-blind, parallel-group, pragmatic randomised controlled trial conducted across five UK sites. We randomly assigned (1:1) adults with co-occurring PTSD and psychosis in secondary care to trauma-focused CBTp plus treatment as usual or treatment as usual only, using randomly varying block size, stratified by site. Trauma-focused CBTp is a flexible, individualised, formulation-based therapy integrating trauma-focused therapeutic components with CBTp, lasting 9 months.
The primary outcome was PTSD symptom severity, assessed using clinician-administered PTSD scale for DSM-5 (CAPS-5), at 4 months (mid-therapy) and 9 months (primary endpoint). Secondary outcomes were (1) percentage of participants showing PTSD remission from diagnosis and clinically significant change, individual symptom clusters, post-traumatic cognitions, and dissociation; (2) psychosis symptoms; (3) mood disorders; (4) psychological recovery; and (5) social functioning, assessed at the same timepoints.
We used linear mixed models in the intention-to-treat population at 9 months, incorporating all outcome data including at 4 months. Lived experience experts were integral throughout the research. This study was registered prospectively with ISRCTN, ISRCTN93382525.
Findings
Between Oct 1, 2020, and March 20, 2023, we randomly assigned 305 participants (151 [49·5%] to treatment as usual and 154 [50·5%] to trauma-focused CBTp plus treatment as usual). The mean age of participants was 38·9 years (SD 12·4). 127 (42%) participants were men, 171 (56%) were women and seven (2%) were non-binary or preferred not to say; 232 (76%) were White. All reported repeated and multiple traumas. Of 154 in the trauma-focused CBTp plus treatment-as-usual group, 144 (94%) engaged with therapy and 146 (95%) received a minimal therapeutic dose. 267 (88%) of 305 participants attended a follow-up assessment (4 months, 9 months, or both); at 9 months, 241 (79%) participants provided primary outcome data and 169–248 (55–81%) provided secondary outcome data.
There were significant effects on CAPS-5 scores (adjusted mean difference in PTSD symptom severity –8·67 [95% CI –13·41 to –3·94]; p=0·0003; Cohen’s d –0·73) and on 22 (81%) of 27 secondary outcomes, unadjusted for multiple testing (Cohen’s d ranging from –0·26 to –0·82), including all PTSD outcomes (except derealisation and depersonalisation); delusions, paranoia, and hallucinations in other modalities; suicidal ideation, depression, anxiety, and stress; and psychological recovery.
There were no effects on voices, referential beliefs, substance use, or social functioning (Cohen’s d ranging from –0·05 to –0·28). 62 (50%) of 125 participants in the therapy group showed PTSD remission compared with 25 (22%) of 116 in the treatment-as-usual group (odds ratio [OR; PTSD present] 0·11, 95% CI 0·03–0·32; p=0·0001) and 56 (45%) participants in the therapy group compared with 31 (27%) in the treatment-as-usual group had clinically significant change in CAPS-5 score (OR 4·45, 95% CI 1·59–12·44; p=0·0044; number needed to treat for PTSD remission was 4). No serious adverse event was unexpected and related to trial procedures (78 reported in each group), with the most common being physical illness or injury.
Interpretation
Trauma-focused CBTp is safe, highly acceptable, and effective in people with co-occurring psychosis and PTSD. This underserved population should no longer be denied access to psychological interventions to treat their trauma sequelae.
Funding
UK National Institute for Health and Care Research (Health Technology Assessment).
