RETN and psoriasis: Subgroup analysis based on ethnicity revealed that serum resistin levels were significantly higher in psoriasis patients, compared to healthy controls, in both Asians and Caucasians (Asians: SMD = 3.27, 95%CI = 1.62 ~ 4.91, P < 0.001; Caucasians: SMD = 0.91, 95%CI = 0.28 ~ 1.54, P < 0.001) (Figure 4A).