Development of a questionnaire for the diagnosis of Qi stagnation.

The objective of this study was to develop a questionnaire for the diagnosis of Qi stagnation. At first, we made the preliminary version of the questionnaire from 30 symptoms most frequently mentioned about Qi stagnation in classic books of Oriental Medicine. Two hundred and seven participants completed the preliminary version of the questionnaire rating the severity of 30 symptoms. Those participants were assessed for Qi stagnation by 2 physicians. Logistic regression analysis was performed between the physicians' assessment of Qi stagnation and the severity of symptoms in the preliminary questionnaire. The final version of the questionnaire was developed with 23 symptoms that had significant odds ratios. The Cronbach's α coefficient was 0.83. The area under the curve was 0.90 and cut-off value for diagnosis of Qi stagnation was 28.5 in receiver operating characteristic (ROC) analysis. Sensitivity and specificity were 0.83 and 0.80, respectively. The Spearman's correlation coefficient was 0.72 in the test-retest. This questionnaire would enable standardization and objective verification of the diagnosis of Qi stagnation.