Multivariate regression analyses of the methadone dose and S-EDDP/methadone dose ratio.

HCV Ab, hepatitis C virus antibody; , regression coefficient; SE, standard error of regression coefficient; VIF, variance inflation factor.HCV Ab（hepatitis C virus antibody，丙型肝炎病毒抗体）；回归系数（regression coefficient）；SE（standard error of regression coefficient，回归系数标准误）；VIF（variance inflation factor，方差膨胀因子）。