Symptom characteristics and prevalence of qi deficiency syndrome in people of varied health status and ages: A multicenter cross-sectional study

Objective: Aging caused by a deficiency syndrome can be found in ancient and modern traditional Chinese medicine literature. Qi deficiency syndrome (QDS) is a vital factor in the aging process. This study aimed to establish a full-scale trial to evaluate the prevalence, symptom severity, frequency, and distribution of QDS in different age groups and varying health status to elucidate the role of qi deficiency in the aging process and deterioration of health. Methods: This cross-sectional study was conducted in four hospitals in China, and data from 1220 participants were included. The participants, aged between 20 and 79 years, completed questionnaires that recorded prevalence of QDS and severity or frequency of relevant symptoms, then were interviewed by investigators. We used frequency analysis and chi-squared tests to perform comparative analysis of prevalence in different age and health groups; we used a rank-sum tests for quantitative analysis of symptoms severity and frequency scores; we performed a regression analysis of correlation between syndrome occurrence and potential factors using non-conditional binary logistic stepwise regression of numerical variables. P