ISRCTN12668007.

Trial name or title	The Nightmare Intervention Study: a pilot randomised controlled trial of a brief cognitive behavioural therapy for nightmares for patients with persecutory delusions
Methods	Allocation: randomised Blinding: not reported Duration: not reported Location: not reported Length of follow‐up: not reported
Participants	Diagnosis: not reported Total: N = N/A Sex: not reported Age: not reported Length of illness: not reported Inclusion criteria: participants experiencing regular nightmares, persistent persecutory delusions, and having a diagnosis of non‐affective* (not related to disturbance of mood) psychosis (e.g. schizophrenia) Exclusion criteria: not reported
Interventions	1. CBT plus standard care group 2. Standard care group
Outcomes	Acceptability and feasibility of the intervention and recruitment and retention rates Nightmare severity ‐ Distressing Dreams and Nightmare Severity Index Psychological well‐being ‐ Warwick Edinburgh Mental Wellbeing Scale Persecutory beliefs ‐ Green Paranoid Thoughts Scale Hallucinatory experiences ‐ Cardiff Anomalous Perceptions Scale Affect ‐ Depression Anxiety and Stress Scale ‐ 21‐item version Symptoms of insomnia ‐ Sleep Condition Indicator Sleep quality ‐ Pittsburgh Sleep Quality Index Dissociative symptoms ‐ Brief Dissociative Experiences Scale
Starting date	November 16, 2015
Contact information	Dr Bryony Sheaves Department of Psychiatry Warneford Hospital Warneford Lane Headington Oxford OX3 7JX United Kingdom +44 1865 226486 bryony.sheaves@psych.ox.ac.uk [mail to:bryony.sheaves@psych.ox.ac.uk]
Notes	Not yet recruiting *We think 'non‐affective' could be schizophrenia, but not necessarily 100%. In this case, we would give this trial the benefit of the doubt and include it.