Episode 57 of CRAMSURG - Clinical Research Appraisal and Methodology for Surgical Trainees. The paper for discussion is Global Use and Outcomes of Endoscopic Stenting in Acute Malignant Left-Sided Colonic Obstruction: A Secondary Analysis of APOLLO, An International, Prospective Cohort Study Dis Col Rec Oct 2025. The teaching topic is a practical guide to statistical tests - part 9: Kendall's correlation coefficient. Brought to you by CRAMSURG www.cramsurg.org.