Common traditional Chinese medicine therapies for diarrhea-predominant irritable bowel syndrome: An overview of systematic reviews

Objective:To critically evaluate and summarize the methodological quality of systematic reviews(SRs)and present objective and important outcomes on the effectiveness of traditional Chinese medicine(TCM)therapies,including Chinese herbal medicine(CHM),acupuncture,and moxibustion,for diarrhea-predominant irritable bowel syndrome(IBS-D).Methods:We conducted a comprehensive literature search for SRs in 7 databases until April 16,2022.Two reviewers independently extracted data and assessed the methodological quality of the reviews according to the Assessing the Methodological Quality of Systematic Reviews 2(AMSTAR-2),the Risk of Bias in Systematic reviews(ROBIS)tool,and the Preferred Reporting Item for Systematic Review and Meta-analysis(PRISMA)statement.The Grading of Recommendations,Assessment,Development,and Evaluation(GRADE)was used to rate the quality of evidence.Results:IBS-D patients included in 12 reviews were diagnosed in accordance with the Rome criteria,9 reviews focused on CHM,2 articles observed moxibustion and heat-sensitive moxibustion,1 article studied acupuncture and CHM.The outcomes of the SRs were the effectiveness rate,the total effectiveness rate,global symptom improvement,and adverse effects.Based on AMSTAR-2,which measures the quality of methodology,all of the included studies were of low or critically low quality.According to the ROBIS tool,10 SRs(83.33％)had a high risk of bias.With the PRISMA checklist,only 3 SRs reached over 90％compliance.Based on GRADE,most evidence was of low quality,and there was a moderate quality of evidence that the effectiveness rate of modified-Tongxie Yaofang was superior to Western medicine in the treatment of IBS-D.Conclusion:Given the suboptimal reporting and methodological quality of existing SRs,more studies are needed to clarify whether TCM therapies are more effective or safe than pharmacological medicine.Future studies should combine evidence-based medicine with TCM research according to the charac-teristics of TCM.