Xuesong Yang

Background: There are approximately five Zhengs reported in psoriatic patients. Systematic data collection and proper analysis for the classification of psoriasis have been lacking. This study aims to cluster the Zhengs in psoriatic patients based on the application of a checklist of traditional Chinese medicine (TCM) symptoms and signs followed by latent class analysis (LCA). Methods: A cross-sectional study of 507 psoriatic patients aged above 10 years was performed in Yunnan Provincial Hospital of TCM and the First Affiliated Hospital of Kunming Medicine University from October 2010 to September 2011 using a TCM symptoms and signs checklist obtained from 16 TCM experts by the Delphi technique. LCA was applied to obtain the best fitted model for clustering of symptoms and signs that can be interpreted as underlying Zhengs of psoriasis. Results: The LCA identified three Zhengs: dampness-heat Zheng (35.1%); blood heat Zheng (34.7%); and yin deficiency and blood dryness Zheng (30.2%). The first Zheng was associated with winter, the second with male sex, old age, smoking, and drinking alcohol, and the third with outpatient status, which reflected a mild disease course. Conclusions: In this study, 507 psoriasis patients were clustered into three Zheng s, which had different associated factors.

Background: Psoriasis is a chronic inflammatory skin disease with a genetic basis. Its ill-defined causes make it difficult to diagnose. This study aims to develop a diagnostic checklist for psoriasis classification in the context of traditional Chinese medicine. Methods: A Delphi study was conducted with three rounds by a panel of 16 dermatology experts to develop a checklist for traditional Chinese medicine symptoms and signs of psoriasis. Dermatology experts in psoriasis research, nine in Yunnan and seven in Beijing, were selected as the expert panel. The initial list of symptoms and signs in psoriasis was developed by reviewing the literature retrieved from Chinese and English journals. Experts rated each item of the list on a 5-point Likert scale. The list was revised and re-evaluated in the same manner for a total of 3 rounds before it was finalized. Results: One hundred and thirty items were extracted from the literature review. After three rounds of expert ratings, 96 items were retained with eight domains: color, type and shape of skin lesion, physical expression, tongue and coating, pulse, associated factors, and living environment. Intraclass correlation coefficient and Kappa statistics indicated an inter-rater agreement in the final checklist. Conclusion: A checklist containing 96 items in 8 domains was developed for psoriasis diagnosis using traditional Chinese medicine symptoms and signs.