Is deqi an indicator of clinical efficacy of acupuncture? A systematic review

Objective. Despite the systematic literature review of the current evidence, we aim to answer the question " is Deqi an indicator of clinical effects in acupuncture treatment?" Methods. We systematically searched CNKI, VIP, Wanfang Data, PubMed, Embase, and the CENTRAL for three types of study: (1) empirical research probing into the role of Deqi in acupuncture; (2) mechanism studies examining the effect of Deqi on physiological parameters in animal models and human subjects; (3) clinical studies that compared the outcome of acupuncture with Deqi with that of acupuncture without Deqi. Two reviewers independently extracted data, undertook qualitative or quantitative analysis, and summarized findings. Results. The ancient Chinese acupuncturists valued the role of Deqi as a diagnostic tool, a prognosis predictor, and a necessary part of the therapeutic procedure. Findings from modern experimental research provided preliminary evidence for the physiological mechanism that produced Deqi. Few clinical studies generated conflicting evidence of the comparative effectiveness of acupuncture with Deqi versus acupuncture without Deqi for a variety of conditions. Conclusion. The current evidence base is not solid enough to draw any conclusion regarding the predicative value of natural Deqi for clinical efficacy or the therapeutic value of manipulation-facilitated Deqi.