Beal EW, Saunders ND, Kearney JF, Lyon E, Wei L, Squires MH, Jin LX, Worhunsky DJ, Votanopoulos KI, Ejaz A, Poultsides G, Fields RC, Swords D, Acher AW, Weber SM, Maithel SK, Pawlik T, Schmidt CR. Accuracy of the ACS NSQIP Online Risk Calculator Depends on How You Look at It: Results from the United States Gastric Cancer Collaborative. Am Surg. 2018 Mar 01; 84(3):358-364.