Trauma-focused Therapies for Posttraumatic stress In Psychosis:
the RE.PROCESS randomised controlled trial

Positive effects on PTSD, psychosis, adversities and revictimization were found
in patients with psychosis for a small dose (8 sessions) of prolonged exposure
(PE) or Eye Movement Desensitization and Reprocessing (EMDR). Replication is
needed and there are many important issues that warrant further investigation,
such as a test of a full treatment dose, improvement of the effects on
psychosis symptoms, and an improvement of our understanding of mechanisms of
change. Importantly, there is need for a head-to-head comparison of
trauma-focused treatments with and without direct trauma memory processing in
patients with psychosis.

Our primary objective is to test the effects on researcher-rated severity of
PTSD symptoms of a full dose of prolonged exposure therapy (PE), eye movement
desensitization and reprocessing therapy (EMDR), cognitive restructuring
therapy without direct trauma memory processing (CR), and waiting list (WL). We
will compare all arms, and are primarily interested in comparing the active
treatments (PE, EMDR and CR) to WL, and in comparing the interventions with (PE
and EMDR) to the intervention without (CR) direct memory processing.
The secondary objective is to investigate the effects of these treatments on
researcher-rated presence of PTSD diagnosis, self-rated severity of PTSD and
severity of complex PTSD symptoms, posttraumatic cognitions, dissociation,
depression, paranoia, auditory verbal hallucinations, social functioning,
disruption of social functioning by PTSD symptoms, resilience, personal
recovery, sexual functioning, adversities, and revictimization. Third, with the
24-month follow-up we aim to test the long-term effects on all the outcomes for
the first time.
Fourth, we aim to explore how post-traumatic stress and psychosis interact
dynamically, how the experimental treatments influence these interactions, and
what factors significantly predict treatment response.
Our fifth objective is to determine the cost-effectiveness of the
interventions.
Sixth, we will conduct a process evaluation of the therapy process by
conducting interviews to examine how participants experienced receiving
trauma-focused treatment.

A single-blind multicentre randomised controlled trial with four arms: PE,
EMDR, CR, and WL. All groups receive treatment as usual for psychosis. All the
groups will be assessed at baseline (T0), mid-treatment (T1), posttreatment
(T2), and at 6-month follow-up (T3). These assessments will take about 90
minutes to administer. Participants in the WL condition can choose to undergo
treatment of choice after the 6-month follow-up assessment. The PE, EMDR and CR
conditions will also be assessed at 12-month and 24-month follow-up. Up to the
6-month follow-up assessment, all groups weekly monitor the outcomes social
functioning, adversities, and revictimization. Participants in the active
treatment arms will receive two treatment sessions per week.

The PE, EMDR and CR groups will receive a maximum of 16 sessions of treatment.
The third group will be a waiting list group up to the 6-month follow-up, after
which they may choose to receive treatment. All groups receive treatment as
usual for psychosis

Participants in the active treatment arms will be tested five times. The
participants will receive a maximum of 16 trauma-focused treatment sessions of
maximally ninety minutes. Some patients may experience a short increase in
symptoms during or following the sessions. Based on prior research, no major
adverse events are expected. CR was found to be safe in patients with
psychosis, and both PE and EMDR were actually found to reduce adversities in
this group. Participants in the WL condition will have to wait for treatment
for 6 months.