Reporting quality and risk of bias assessment of animal research on Chaihu-Shugan-San for depression: A systematic review

OBJECTIVE: Chaihu-Shugan-San (CSS) is a traditional Chinese medicine formula employed to treat depression. We aim to conduct a reporting quality assessment and risk of bias evaluation of animal research on CSS for depression. METHODS: To acquire eligible studies, two reviewers searched plentiful databases from inception to October 23rd, 2021. Reporting quality assessment and risk of bias assessment of the included animal studies were evaluated by using Animal Research: Reporting In Vivo Experiments (ARRIVE) guidelines and the SYstematic Review Centre for Laboratory animal Experimentation (SYRCLE) risk of bias tool, respectively. RESULTS: The initial search identified 720 records, while only 30 studies were included. The result of the reporting quality assessment was inferior, items 17 and 19 were not reported at all. The details of five items (items 3, 6, 7, 10, and 18) were not reported. The outcome of the risk of bias assessment suggested that half of the entries (5/10) displayed an unclear risk of bias and a high risk of bias. Blinding with regard to performance bias and detection bias revealed an unclear risk of bias (100%), followed by baseline characteristics (76.67%) and sequence generation (60%). Random outcome assessment showed a high risk of bias (100%). CONCLUSION: The included animal studies exhibited methodological defects and imprecise reporting. Hence, the ARRIVE guidelines and SYRCLE's RoB tool should be disseminated among basic medical researchers examining CSS for depression to publish studies with low risk of bias and sufficient reporting so that the animal research can promptly be transformed into clinical research.