Background: To evaluate the usefulness of preoperative screening for coagulation disorders in children who have undergone surgery.Methods: From January 2003 to December 2005, we prospectively evaluated laboratory and bleeding histories in 1,911 children between the ages of one year and 15 years. All of the patients had preoperative coagulation screening with a measurement of complete blood count, prothrombin time and activated partial thromboplastin time. The sensitivity, specificity and positive and negative predictive values following a preoperative coagulation-screening test were evaluated by a comparison of the type of surgery and bleeding complications that occurred during and after surgery.Results: There were no patients with previously proven coagulopathies or suspicious medical histories. Among the 1,911 cases, a subset of 22 patients had persistent abnormalities detected after laboratory testing. In two of the 22 patients, lupus anticoagulant was detected and in one of the 22 patients, a factor VIII deficiency was discovered. There were 46 patients that had postoperative bleeding and required hospitalization extension or readmission for stanching. Among the 46 patients, 44 patients demonstrated normal coagulation after testing and two patients demonstrated abnormal coagulation after testing. Following a preoperative coagulation-screening test, a low sensitivity (0.04) and positive predictive value (0.09) were determined.Conclusion: For the prediction of perioperative bleeding, the use of a coagulation-screeningtest showed a very low positive predictive value. Many false positive laboratory tests coupled with the relative rarity of inherited and acquired coagulopathies raises doubt about the overall value of routine preoperative coagulation screening in children. (Korean J Hematol 2008;43:98-105.)

Keywords: Blood coagulation test, Prothrombin time, Partial thromboplastin time