Psychological interventions for people with psychotic experiences: protocol for a systematic review and meta-analysis

Emma Soneson,Jan S̆tochl ,Leticia González‐Blanco ,David Fowler,Michelle Griffiths,Peter M Jones ,Nick Grey,Alexandros Georgiadis ,Sarah Byford,Joanne Hodgekins,Mary Dixon‐Woods ,Louise Lafortune,Margaret Heslin,Paul French,Debra A Russo ,Robbie Duschinsky,Juliet Couche,Clare Knight,Nesta Reeve,Julieta Galante,Hannah Murray,Jesús Pérez

doi:10.1186/s13643-019-1041-5

Abstract

BackgroundMany people who have common mental disorders, such as depression and anxiety, also have some psychotic experiences. These experiences are associated with higher clinical complexity, poor treatment response, and negative clinical outcomes. Psychological interventions have the potential to improve outcomes for people with psychotic experiences. The aims of this systematic review are to (1) synthesise the evidence on the effectiveness and cost-effectiveness of psychological interventions to reduce psychotic experiences and their associated distress and (2) identify key components of effective interventions.MethodsOur search strategy will combine terms for (1) psychological interventions, (2) psychotic experiences, and (3) symptoms associated with psychotic experiences. We will search the following online databases: MEDLINE, Embase, PsycINFO, all Cochrane databases, British Nursing Index (BNI), Cumulative Index to Nursing and Allied Health Literature (CINAHL), Health Management Information Consortium (HMIC), Education Resources Information Center (ERIC), and EconLit. Our primary outcome is the proportion of people who recovered or remitted from psychotic experiences after the intervention. Our secondary outcomes are changes in positive psychotic symptoms, negative psychotic symptoms, depression, anxiety, functioning (including social, occupational, and academic), quality of life, and cost-effectiveness. Two independent reviewers will judge each study against pre-specified inclusion and exclusion criteria and will extract study characteristics, outcome data, and intervention components. Risk of bias and methodological quality will be assessed using the Effective Public Health Practice Project Quality Assessment Tool for Quantitative Studies and the Drummond Checklist. Results will be synthesised using random-effects meta-analysis and narrative synthesis.DiscussionThe identification of effective psychological interventions and of specific components associated with intervention effectiveness will augment existing evidence that can inform the development of a new, tailored intervention to improve outcomes related to psychotic symptoms, anxiety and depression, distress, functioning, and quality of life.Systematic review registrationPROSPERO CRD42016033869

Highlights

Many people who have common mental disorders, such as depression and anxiety, have some psychotic experiences
This suggests that common mental disorder with psychotic experiences may represent a distinct form of illness that might benefit from targeted therapeutic approaches
The proposed systematic review will answer the following questions: 1. Which psychological interventions have been effective for the treatment of psychotic experiences and have improved outcomes related to psychotic symptoms, symptoms of depression and anxiety, distress, functioning, and quality of life?

Summary

Methods

Aim The aim of this systematic review is to provide an evidence synthesis of the effectiveness and cost-effectiveness of all psychological interventions to reduce psychotic experiences and the associated distress through meta-analysis, supported by narrative synthesis where appropriate. The synthesis will address Research Question 2 by: Providing a qualitative account of our four a priori components of interest—assessment of problems and goals, formulation, homework, and active change strategies [41]—in relation to intervention effect for studies not included in our meta-analyses. Sensitivity analysis We will perform sensitivity analyses within the metaanalysed studies to explore the effect of studies with a high risk of bias (e.g. studies that do not use intentionto-treat reporting, studies with high attrition, and studies with missing data) We will do this by removing those studies that received a ‘high’ risk of bias rating in any of the bias sections of the Effective Public Health Practice Project Quality Assessment Tool from the meta-analysis and re-computing a pooled estimate of intervention effect. We will use the GRADE working group’s recommendations of four levels of evidence quality: high, moderate, low, and very low [51]

Discussion

Background

Findings