Development and evaluation of short form of constitution in Chinese medicine questionnaire: a national epidemiological survey data of 21 948 cases

BAI Minghua,WONG Wendy,HOU Shujuan,ZHENG Yanfei,LI Qianru,LI ZhuQing,ZHANG Yan,LI Lingru,WANG Ji,WANG Qi

BAI Minghua,School of Traditional Chinese Medicine/National Institute of TCM Constitution and Preventive Medicine,Beijing University of Chinese Medicine,Beijing 100029,China

WONG Wendy,School of Chinese Medicine,Hong Kong Institute of Integrative Medicine,Chinese University of Hong Kong,Hong Kong SAR 852,China

HOU Shujuan,ZHENG Yanfei,LI qianru,LI Zhuqing,ZHANG Yan,LI Lingru,WANG Ji,WANG Qi,National Institute of TCM Constitution and Preventive Medicine,Beijing University of Chinese Medicine,Beijing 100029,China

Abstract OBJECTIVE: To develop the best short form of constitution in Chinese medicine questionnaire (CCMQ)and evaluate its psychometric properties in Chinese population.METHODS: A total of 21 948 subjects were used to refine the short form.Correlation coefficient,exploratory factor analysis (EFA) and Cronbach′s alpha coefficient were used to analyze and select items to form the short form.Separate sample of 205 subjects were collected to further evaluate the short from.EFA,confirmatory factor analysis(CFA),item-scale correlation,discriminant validity,internal consistency reliability and split-half reliability were carried out to evaluate the short form.RESULTS: The short form CCMQ included 26 items.Seven common factors of characteristic root ＞ 1 were extracted to explain 58.488% of the total variation.Result of CFA was consistent with the 9-factors structure.The mean differences of Blood-stasis body constitution and Qi-stagnation body constitution had statistical significance in body mass index differentiation.Cronbach′s alpha coefficient of short form CCMQ was 0.863.The split-half reliability of total scale was 0.813,and each scale was 0.568-0.770.The item-scale correlations ranged from 0.620-0.849.CONCLUSION: The short form CCMQ consisted of 26 items with good psychometric properties.The short form should be recommended for the measurement of health of Chinese population in any clinical trial.

Keywords: constitution in Chinese medicine questionnaire;form;scale evaluation;reproducibility of results

Table 1 Comparison of the original and the short form of the CCMQ (n=21 948)a

Table 1 Comparison of the original and the short fbrm of the CCMQ (n = 21 948)a (continued)

Table 2 The total variance of short form CCMQ (n = 204) a

Table 3 EFA, CFA and item-scale of the short form CCMQ (n = 204)

Table 4 Goodness of fit statistics for the short form CCMQa

Figure 1 Results of confirmatory factor analysis

Table 5 Discriminant validity and reliability of the short form CCMQ