Experimental studies of paranoid thinking in clinical and nonclinical populations: a systematic review and meta-analysis.

Paranoia is common in clinical and nonclinical populations, consistent with continuum models of psychosis. A number of experimental studies have been conducted that attempt to induce, manipulate or measure paranoid thinking in both clinical and nonclinical populations, which is important to understand causal mechanisms and advance psychological interventions. Our aim was to conduct a systematic review and meta-analysis of experimental studies (non-sleep, non-drug paradigms) on psychometrically assessed paranoia in clinical and nonclinical populations. The review was conducted using PRISMA guidelines. Six databases (PsycINFO, PubMed, EMBASE, Web of Science, Medline and AMED) were searched for peer-reviewed experimental studies using within and between-subject designs to investigate paranoia in clinical and nonclinical populations. Effect sizes for each study were calculated using Hedge's g and were integrated using a random effect meta-analysis model. Thirty studies were included in the review (total n = 3898), which used 13 experimental paradigms to induce paranoia; 10 studies set out to explicitly induce paranoia, and 20 studies induced a range of other states. Effect sizes for individual studies ranged from 0.03 to 1.55. Meta-analysis found a significant summary effect of 0.51 [95% confidence interval 0.37-0.66, p < 0.001], indicating a medium effect of experimental paradigms on paranoia. Paranoia can be induced and investigated using a wide range of experimental paradigms, which can inform decision-making about which paradigms to use in future studies, and is consistent with cognitive, continuum and evolutionary models of paranoia.

Exploring how to improve access to psychological therapies on acute mental health wards from the perspectives of patients, families and mental health staff: qualitative study.

BACKGROUND: Psychological therapy is core component of mental healthcare. However, many people with severe mental illnesses do not receive therapy, particularly in acute mental health settings. AIMS: This study identifies barriers to delivering and accessing psychological therapies in acute mental health settings, and is the first to recommend how services can increase access from the perspectives of different stakeholders (staff, patients and carers). METHOD: Sixty participants with experiences of acute mental health wards (26 staff, 22 patients and 12 carers) were interviewed about barriers to accessing therapy in in-patient settings and how therapies should be delivered to maximise access. RESULTS: Four themes were identified: (a) 'Models of care', including the function of in-patient wards, beliefs about the causes of mental health problems and the importance of strong leadership to support psychosocial interventions; (b) 'Integrated care', including the importance of psychologists being ward-based, as well as having strong links with community teams; (c) 'Acute levels of distress', including factors that aggravate or ameliorate the impact of this on engagement in therapy; and (d) 'Enhancing staff capability and motivation', which is influenced by contextual issues. CONCLUSIONS: It is possible to improve access to therapy through strong leadership (that is supportive of talking treatments), flexible delivery of therapy (that considers short admissions) and a whole-systems approach that promotes ward staff understanding of the psychosocial causes of mental illness and staff well-being. It is essential to ensure continuity between in-patient and community therapy services, and for wards to have physical space to carry out therapy.