validity of Hy Law in the prospective DILI Network (DILIN) cohort. METHODS: Drugs with ≥10 confirmed DILI cases with jaundice were analyzed. Four permutations of Hy Law were applied: R ≥ 5 using initial (1) or peak (2) alanine aminotransferase, aspartate aminotransferase and alkaline phosphatase levels, and the Food and Drug Administration associated criteria of alanine aminotransferase or aspartate aminotransferase ≥ 3x upper limit of normal with alkaline phosphatase ≤ 2x upper limit of normal using initial (3) or peak values (4). Mortality was death or liver transplant adjudicated to be due to DILI. RESULTS: Using initial R values, mortality was 11.1% for HC vs 2.0% for C/M (P < 0.001); using peak R values, mortality was 10.3% vs 1.6% (P < 0.001). Using Food and Drug Administration-associated definition, mortality was 7.9% vs 3.9% (P = 0.04) using initial values and 7.9% vs 3.0% (P = 0.01) using peak values. Using initial R values, drugs that frequently caused HC injury generally had