Protocol for the evaluation and validation of Qi Blood Yin Yang deficiency pattern questionnaire: prospective observational study

BACKGROUND The aim of this study is to validate the pattern identification standard of qi, blood, yin, and yang deficiency patterns diagnosis. The current study will investigate the usefulness of the Qi Blood Yin Yang deficiency pattern questionnaire as a diagnostic tool for qi, blood, yin, and yang deficiencies by assessing the agreement between the scores and a gold standard established by assessors. METHODS This protocol is for a single center, prospective, observational study. A total of 248 eligible patients with unexplained chronic fatigue will be assigned to four groups in a 1:1:1:1 ratio as the qi deficiency group, blood deficiency group, yin deficiency group, and yang deficiency group. The primary outcome will be measured using the score of the Qi Blood Yin Yang deficiency pattern questionnaire and the secondary outcomes will be measured using the fatigue severity scale, Korean-translated chalder fatigue scale, computerized tongue image analysis system, and three types of pattern identification questionnaires (cold-heat, food accumulation, and seven emotions patterns). The safety of the clinical study will be assessed after measurements at every visit. All statistical analysis will be performed using the R Statistics program. Statistics experts will analyze the relationship between clinical data using the Pearson's Chi-squared test and independent t-test. DISCUSSION This study will provide reference data and good evidence that are applicable to future studies. Furthermore, the results of the present study are useful to improve the care of patients with unexplained chronic fatigue and unexplained chronic fatigue-related disorders.