CHI3L1 and fatty liver disease: Previous studies have shown AUC values of 0.63 for individual biomarkers such as fatty liver index [43] or 0.59 for tissue inhibitor of metalloproteinase 1 (TIMP 1), 0.73 for hyaluronic acid, 0.67 for cytokeratin-18, and 0.62 for human cartilage glycoprotein 39 (also known as YKL-40) [44] in individuals with NASH.