Cognitive behavioural treatment of insomnia in individuals with persistent persecutory delusions: A pilot trial

► First ever test of the effects of an insomnia reduction intervention for patients with persistent persecutory delusions. ► There were large reductions in both insomnia and persecutory delusions. ► The reductions persisted at one-month follow-up. ► The intervention is brief (4 sessions) and uses basic CBT for insomnia techniques, meaning that it can be easily disseminated. ► The results support the theoretical idea that insomnia is a causal factor in paranoid experiences.