Effectiveness of community-based interventions for patients with schizophrenia spectrum disorders: a study protocol for a systematic review

Background: Schizophrenia requires a community-based intervention approach combined with standard treatment to prevent relapses. A literature review is required to understand the effectiveness of community-based interventions and to enhance quality in countries where they have not been fully established. This is a protocol for a systematic review of the effectiveness of community-based interventions for patients with schizophrenia spectrum disorders. Methods: We will search (from inception to January 2021) PubMed/MEDLINE, EMBASE, PsycINFO, CENTRAL, CINAHL, and Research Information Sharing Service/Korean databases. Randomized controlled trials on community-based interventions for patients with schizophrenia spectrum disorders will be eligible. The comparison groups will include patients with schizophrenia spectrum disorders who are only receiving the usual care and those who also receive community-based interventions. The schizophrenia spectrum disorders referred to in this study are defined according to the DSM-5: delusional disorders, schizophrenic disorders, and schizoaffective disorder will be included. Relapse/re-hospitalization rates (primary outcome) and quality of life (secondary outcome) will be identified for each group. Two reviewers will independently screen study titles, abstract data, and full-text articles and perform the data extraction process. Potential conflicts will be resolved through discussion. The study risk of bias will be appraised using the Cochrane Risk of Bias 2.0 tool. Results will be descriptively synthesized and will be structured according to patients' characteristics, intervention type and exposure, and outcome type. If feasible and appropriate, outcome data will be used to perform random effects meta-analyses. Discrete variables will be calculated via odds ratio, and continuous variables will be calculated via standardized mean difference using RevMan 5.3 software. Discussion: We will provide a summary of the available evidence on the effectiveness of community-based interventions and specific guidelines to improve their outcomes.