Logistic regression 可以找 thresholds  （The Wilcoxon rank-sum test for continuous measures and Fischer’s exact test for categorical measures were used to compare patient characteristics and outcomes. Logistic regression was used to determine thresholds for discriminating necrotizing pancreatitis from interstitial pancreatitis based on hematocrit at admission and at 24 hours. Similar logistic regression models were used to determine thresholds for the APACHE-II scores calculated at admission and at 24 hours. Receiver operator curves were plotted for the range of hematocrit values. A forward stepwise logistic regression was run to determine the best combination of hematocrit and APACHEII thresholds to predict accurately the development of necrotizing pancreatitis.）