Hangeshashinto for preventing oral mucositis in patients receiving cancer treatment: protocol for a systematic review and meta-analysis.

INTRODUCTION: Hangeshashinto has been employed for oral mucositis prevention in patients receiving cancer treatment, but the evidence has not been sufficiently robust to guide clinical decision-making. This study will therefore be undertaken to assess the effectiveness of Hangeshashinto for preventing oral mucositis in patients with cancer who are receiving treatment. METHODS AND ANALYSIS: The databases will include PubMed, Embase, the Cochrane Library, Chinese databases and Japanese databases. The literature will be searched from the databases' inception until May 2021. Other sources, such as potential grey literature, reference lists from included studies and relevant systematic reviews and conference papers, will also be searched. The primary outcome is the incidence of mucositis of any severity, and the secondary outcomes are interruptions to cancer treatment, oral pain and nutritional status. The risk of bias of eligible studies will be assessed using the Cochrane Collaboration's 'risk of bias' tool. Both the Q test and I(2) statistic will be performed to assess statistical heterogeneity. If I(2) >50%, sensitivity and subgroup analysis will be conducted. The quality of evidence will be rated according to the Grading of Recommendations, Assessment, Development and Evaluation approach. Egger's test will be used to assess reporting bias. ETHICS AND DISSEMINATION: This systematic review will evaluate only published data; therefore, ethical approval is not required. PROSPERO REGISTRATION NUMBER: CRD42020216145.