Pilot and feasibility trials in traditional Chinese medicine: a literature review of current practice

BACKGROUND: The guidelines for pilot and feasibility studies were published in 2016. Little is known about the guideline adherence of TCM (traditional Chinese medicine) pilot trials or whether the guidelines can significantly enhance the quality of implementation and reporting of TCM pilot trials. We aimed to investigate the guideline adherence, assess the impact of guidelines on TCM pilot trials, and discuss potential challenges specific to TCM pilot trials, by conducting a literature review. METHODS: We systematically searched MEDLINE, EMBASE, and CNKI to retrieve TCM pilot trials. We randomly chose 50 pilot trials from the eligible studies for analyses. The CONSORT extension to pilot and feasibility studies was used as a framework to assess the methodology and reporting quality of the studies. RESULTS: The included studies had a guideline adherence level ranging from 4 to 96%, where the lowest adherence was found in the item 6c (prespecified criteria used to judge progression to future definitive trial). The guidance published in 2016 seemed to exert minimal effect on guideline adherence in TCM pilot trials. The unidentified issues related to TCM pilot trials from the guidelines included blinding, lack of standard formula of interventions, difficulty in comparison for effect assessment of interventions, and difficulty in bias control. CONCLUSIONS: The current practice in TCM pilot trials required substantial improvement in the literature. Further endeavors are needed for training and dissemination of guideline adherence, and development of more detailed methodology in the field of TCM pilot trials.