Reliability of Manual Pulse Diagnosis Methods in Traditional East Asian Medicine: A Systematic Narrative Literature Review

BACKGROUND/OBJECTIVE: Little evidence shows the reliability of Chinese medicine pulse diagnosis. Regularly used in modern practice, it is believed to gather important diagnostic information. However, in the current evidence-based healthcare system, basing clinical decisions on unproven methods is problematic and obviously questions the relevancy of the procedure. Therefore, the literature on reliability of practitioners implementing the method was reviewed. METHODS: Major medical databases and reference lists of identified articles were searched. All studies published in English that investigated manual pulse diagnosis applied to the radial artery by human testers were considered. RESULTS: Twelve eligible studies were included; three evaluated intra- and inter-rater pulse diagnosis reliability, and nine assessed inter-rater reliability. Acceptable levels of intra- and inter-rater reliability were achieved with operationally defined methods. Poor reliability was related to unclear definitions and terminology existing within the classical definitions, and with standardized systems to persisting imprecise descriptions that can be interpreted differently. Reliability of pulse qualities was influenced by sensation complexity and the amount of sensory input provided to the testers' fingers by the impulse. Consistent study limitations included small sample sizes; the possibility that testers' prior knowledge confounded the data; and, most notably, the fact that many studies did not consider intra-rater reliability. Assessing the effectiveness of interventions in clinical practice is guided by comparisons of markers to baseline. The absence of intra-rater results may therefore raise methodologic concerns for these types of studies. CONCLUSION: Strategies for future studies include using pulse methods with concrete operational definitions; investigating intra- and inter-rater reliability for extrapolation to clinical practice; similar training and experience in the method to control for tester variance; maintaining independence of the data by ensuring testers have no prior knowledge of the participants' pulses; and for more rigorous testing, consideration of the number of pulse variables, participants, and testers.