【Objective】To establish a simple and practical system to predict the prognosis of acute-on-chronic liver failure (ACLF). 【Methods】 All 558 patients with acute-on-chronic hepatitis B liver failure were divided into death group and survival group according to the clinical outcome. And all the patients were also divided into training samples (n=499) and testing samples (n=59) with a ratio of 9:1. Univariate analysis was used to screen the most influential independent risk factors. Each factor was given a certain score. A prognosis scoring system was established based on these factors with the method of discriminant analysis. A Fisher’s discriminant formula and discriminant value were obtained. The efficacy of discriminant formula was checked with retrospective validation and cross-validation in training sample and prospective validation in testing sample. 【Results】 Univariate analysis showed statically significant index including age

the pre-existing cirrhosis

aspartic transaminase levels

et al. Finally

six factors (level of serum total bilirubine

prothrombin time

severity of hepatic encephalopathy

hepatorenal syndrome

ascites and infection) which were easier to evaluate and more influential

were included to establish a prognosis scoring system. Using this scoring system

the patients with a score of 6

7

8

9

10

and ≥11 showed a mortality of 34.9%

66.7%

76.7%

85.7%

91.7%

and 100%

respectively. The efficacy of prediction of discriminant formula was 75.1%-88.9% in training samples and 74.3%-88.0% in testing samples. 【Conclusions】 In dynamic assessment

the prognosis scoring system we established here was simple

practical and efficient when predicting the prognosis of patients with ACLF.