Potential research priorities for understanding and treating severe paranoia (persecutory delusions): a priority-setting partnership between patients, carers, mental health staff, and researchers

A persecutory delusion (severe paranoia) occurs when a person believes that others are trying to harm them when they are not. It is often a central difficulty for patients diagnosed with schizophrenia. The objective is to identify potentially important research questions about severe paranoia. A priority-setting partnership exercise was conducted involving people with lived experience, carers, mental health staff, and researchers. An initial survey identified research questions, and a second survey prioritised a refined list of questions. There was a project steering group. 1480 responses were gathered from 146 people (56 people with lived experience, 23 family members, 78 mental health staff, and 21 researchers). Following refinement, 201 questions were rated by the steering group for priority to enter the second survey. 38 questions were rated in the second survey by 157 people (69 people with lived experience, 33 family members, 59 mental health staff, and 27 researchers). 15 questions were identified as research priorities, each endorsed to a largely similar extent across stakeholder groups. These covered a wide range of topics, including how to support family and carers, understanding the causes of paranoia, managing paranoid thoughts day-to-day, improving access to services, and developing psychological and pharmacological approaches. There was a good deal of consensus in key questions-covering many aspects of understanding, treatment, and support-to be answered about severe paranoia. Most questions were considered largely equally important. Numerous questions were identified that, if addressed, might improve clinical provision for persecutory delusions.