CYP27B1 and systemic lupus erythematosus: There was no significant difference in the mRNA expression of CYP27B1 between the no-steroid and low-dose steroid subgroups (t = 1.997, p = 0.053), between the no-steroid and medium-dose steroid subgroups (t = 1.94, p = 0.847), and between the low-dose steroid and medium-dose steroid subgroups (F = 0.723, p = 0.485) in the stable-disease cohort, and between the medium-dose steroid and high-dose steroid subgroups (t = 0.825, p = 0.417) in the active-SLE cohort.