Abstract: A case-control study has been carried out on 97 vulgaris psoriasis patients as experimental group compared with 71 dermatological patients withoutpsoriasis as the control group, they were matched for age, sex, occupation,educational level, economic status and residental conditions. 36 variables, con-sisting of 26 psychosocial ratings (MMPI, EPQ, SCL-90 and LES), 7 bio-logical indices and 3 environmental factors, had (Relative Risk), and then14 variables were confirmed as the risk factors on developing psoriasis, TheNon-conditional Logistic Regression Analysis showed that 8 of the 14 varia-bles were associated with developing psoriasis significantly. According topsychology and dermatology knowledge, the causal structure recursive modelof Path Analysis with 8 risk factors for psoriasis was set up. The resultsindicated that 5 psychosocial factors had direct or indirect influence on theoccurence of psoriasis respectively. The path diagram drew the relation ofcoopetation effects among 8 risk factors.

Key words: psoriasis, psychosocial factors, Non-conditional logistic regression analysis, path analysis