The severity of organ failure was classified into 3 grades: grade 1 (no organ failure; EPIC score 0–2), grade 2 (transient organ failure; EPIC score 3–4), and grade 3 (persistent organ failure; EPIC score 5–7). A McNemar–Bowker value of 41.41 was obtained (df = 3, P < .001), with a Kappa value of 0.241 (P < .001). EPIC scores and Atlanta Marshall multiple organ dysfunction scores of AP severity differed significantly (P < .001). Kappa analysis indicated that EPIC scores had only a weak correlation with severity of organ failure. Spearman correlation analysis revealed a moderate correlation of EPIC score with severity of organ failure (r = 0.321, P < .001).