A total of 13 parameters were included in univariate analysis for the risk of liver fibrosis in individuals with HIV/HBV co-infection, including demographic indicators (such as gender and age), HIV associated indicators (such as whether cART, whether HIV-RNA detectable, CD4 levels), HBV associated indicators (such as HBsAg titer, HBeAg and HBeAb status, whether HBV-DNA detectable), ALT, AST and PLT levels. The gene discussed is CD4; the disease is coinfection.