Efficacy of non-pharmacological interventions on depressive symptoms in patients with Parkinson's disease: a study protocol for a systematic review and network meta-analysis

IntroductionDepression is the most dominant non-motor symptom of Parkinson's disease (PD), with a prevalence of up to 50%, and can lead to a range of psychiatric and psychological problems that can affect quality of life and overall functioning. While several randomised controlled trials (RCTs) have tested the effect of certain non-pharmacological interventions on the outcome of PD depression symptoms, the comparative benefits and harms of these remain unclear. We will conduct a systematic review and network meta-analysis to compare the efficacy and safety of different non-pharmacological interventions for patients with PD depression.Methods and analysisWe will search PubMed, Web of Science, Cochrane, Embase, Google Scholar, the Chinese National Knowledge Infrastructure, the Chinese Biomedical Literature Database, WanFang Data and the Chongqing VIP Database from their inception date to June 2022. The studies will be limited to results published in English or Chinese. The primary outcomes will be the changes in the depressive symptoms, while secondary outcomes will include adverse effects and the quality of life. Two researchers will screen those documents that meet the inclusion criteria, extracting data according to the preset table and evaluating the methodological quality of the included studies using the Cochrane Risk of Bias 2.0 Tool. The STATA and ADDIS statistical software will be used to conduct a systematic review and network meta-analysis. A traditional pairwise meta-analysis and a network meta-analysis will be performed to compare the efficacy and safety of different non-pharmacological interventions, ensuring the robustness of the findings. The Grading of Recommendations Assessment, Development and Evaluation system will be used to assess the overall quality of the body of evidence associated with the main results. The publication bias assessment will be conducted using comparison-adjusted funnel plots.Ethics and disseminationAll the data for this study will be extracted from published RCTs. As a literature-based systematic review, this study does not require ethical approval. The results will be disseminated through peer-reviewed journals and national/international conference presentations.PROSPERO registration numberCRD42022347772.