Title: Cognitive Bias Modification for Paranoia: A novel attempt to treat paranoiddelusions
Funder: Department of Health and Social Care

Abstract: Background Mental illness accounts for 23% of disease burden but currently receives only 13% of NHS resources4. Paranoia is associated with a range of mental health conditions, including psychosis. The lifetime rate of psychotic disorders is 3.5%5, meaning in London alone 287,000 people will be afflicted during their lifetime. Psychosis is one of the most disabling mental health conditions6, associated with distress and impairment in work, family and social functioning (Schizophrenia Commission, 2012). Persecutory delusions, the most common form of psychotic delusion, are also prevalent in other disorders and present in around 10-15% of the general population63 . Recent advances favour targeted interventions, focussing on specific symptoms or mechanisms 58, 9. This study proposes to test feasibility of one such intervention, Cognitive Bias Modification for paranoia' (CBM-pa). CBM-pa is a self-administered psychological procedure that has been developed by combining basic research on biases in paranoia61 with established CBM techniques. CBM-pa is computerised and involves reading text inviting paranoid interpretations, but then generating responses reflecting an alternative, non-paranoid interpretation. Several other psychological interventions target cognitive processes in psychosis/paranoia 64-66, but none focus specifically on biased interpretations of emotional ambiguity, or can offer the easy-access flexibility that CBM techniques do. Preliminary work shows that CBM-pa manipulates paranoid biases toward more adaptive processing, as expected. After one session paranoid beliefs are reduced, as is the distress associated with an ambiguous real-life social situation, in people with paranoid traits. A six session version has been developed, with input from service-users. Aims Our aim is to examine whether CBM-pa, in outpatients experiencing paranoia, has patient benefit, would be feasible as a targeted therapy, and to provide justification for a randomised controlled trial (RCT). We will examine acceptability; select outcomes; obtain variance estimates; measure recruitment, retention and follow-up rates and test protocol feasibility. We will gather qualitative interview data on patients experience using CBM-pa, focussing on acceptability and promoting engagement. Question to be addressed We hypothesize the biases CBM-pa manipulates are a maintaining mechanism for patients paranoia. Reducing them should reduce paranoia and associated distress. Specific questions include: 1) Which symptom measure should be the RCT primary outcome 2) What sample size this requires 3) Whether the protocol requires any modifications We do not propose hypothesis testing on outcomes at this stage (NIHR-endorsed guidelines). Nevertheless we would expect to observe a pattern of means consistent with reduction in symptoms and distress, in the intervention group. Plan of investigation We will randomize 60 stabilised outpatients presenting persistent distressing paranoia to either CBM-pa or text-reading control, both in addition to TAU. All participants will receive TAU in the form of individualised combinations of medication, care co-ordination and psychological treatments. This design directly evaluates the hypothesized active ingredient (bias reduction) by using the control condition to match all other aspects of the adjunct intervention. CBM-pa is delivered on computer, set up by researchers, and once running is a self-directed, automated package involving participant input only. Experimental measures serve as manipulation checks for CBM-pa and confirm intervention integrity. Participants will be able to ask questions after each session and upon completion of follow-up full debriefing will be given. Each participant will attend the IoP, or other convenient location, receiving one 40min session per week, for 6 weeks, with 1 and 3 month follow-ups. Assessments (symptoms and bias level) will be conducted at each session to enable investigation of dose effects. Qualitative interviews will be held, after quantitative data collection, with 8 patients who were randomised to CBM-pa.

Lay abstract: Many people with psychosis continue to have paranoid beliefs, despite the best treatments available. We will examine a new computer therapy, Cognitive Bias Modification for paranoia (CBM-pa). CBM encourages people to develop alternative ways of interpreting difficult thoughts (i.e. &ldquo;someone is watching me&rdquo;), leading participants to change their understanding of what these situations might mean. CBM is used in anxiety 62,21, but has not been appropriately applied to other disorders. Our version, CBM-pa, was developed with service-user input. It is based on new research into the biases that people with paranoia have when interpreting events61. It involves participants reading stories on a computer screen, completing missing words and answering questions about each story in a way that encourages more helpful beliefs about themselves and others. After one session of CBM-pa, people with paranoia displayed a range of helpful effects, including significant belief change, and less distress in ambiguous social situations. This study will test whether, in addition to usual treatment, six sessions of CBM-pa produces significant benefit for patients (for example by reducing symptoms and distress) immediately, and at 1 and 3 month follow-up, compared to reading passages of text alone. Eight participants will be interviewed in more depth about their experiences. The overall aim is to test whether CBM-pa could be an effective treatment for paranoia. If so, CBM-pa would have a number of potential advantages over other approaches, including, minimal effort to complete, no homework, no therapist, and portability. Ethical considerations. Participants will take part in addition to receiving treatment-as-usual. The therapy might evoke stress in those presenting paranoia. To address this, participant s mood will be routinely assessed before leaving and follow-up contact with a clinical psychologist offered, if needed. Participants will be fully informed about what the study involves both in writing and verbally.

Research activity codes: 6.6 PSYCHOLOGICAL AND BEHAVIOURAL
Health categories: MENTAL HEALTH