Sequential stepwise regression for Cox PH model selection and maximum likelihood estimates of genetic covariates associated with AIDS progression.

NOTE. AIC, Akaike information criteria; S.E., standard error; RH, relative hazard; CI, confidence interval; dom, dominant genetic model; rec, recessive model.1AIC without covariates (null model) = 1796.32;2The best model with minimal AIC is achieved at the ninth step including first 9 covariates entered.3The X2 value for likelihood ratio test, degree of freedom, 9; P = 6.24×10−13; and shrinkage of the model = (77.04−9)/77.04 = 0.88. All analyses were stratified with age groups that known to modify AIDS progression.