The quality assessment and risk of bias evaluation of animal studies on the use of Chaihu-Shugan-San for depression found significant methodological flaws and poor reporting.
A rigorous review was conducted by two researchers, who searched a multitude of databases from their inception until October 23, 2021, to identify eligible studies. The purpose was to analyze the quality of reporting and the risk of bias in these animal studies, utilizing the Animal Research: Reporting In Vivo Experiments guidelines and the SYstematic Review Centre for Laboratory Animal Experimentation risk of bias tool. From an initial pool of 720 records, only 30 were deemed appropriate for inclusion.
The results showed suboptimal reporting, with certain aspects not documented at all. Half of the criteria evaluated showed an unclear or high risk of bias, including performance bias, detection bias, and sequence generation. It was also noted that assessments of random outcomes carried a high risk of bias. This underlined considerable methodological deficiencies in these animal studies, as well as shortcomings in reporting.
