increase in postsurgical morbidity and mortality associated with the beginning of the academic year. A 2006 Journal of Neurosurgery: Pediatrics study found a small increase in the risks associated with cerebrospinal fluid shunt surgery in children during the months of July and August. A 2003 Obstetrics & Gynecology study found no July effect in obstetric procedures. A 2011 systematic review in the Annals of Internal Medicine found that during year-end changeovers, hospital mortality increases and hospital efficiency decreases. A 2016 study in JAMA Surgery found no evidence of the July effect in patient-experience outcomes in surgical patients. A 2019 study from the Yale School of Medicine found no difference in morbidity or mortality after Whipple procedures (pancreaticoduodenectomy) performed in July compared to the remainder of the academic year. United Kingdom In Britain, there is an influx of newly qualified doctors into the National Health Service (NHS) each August, and this period is associated with an increase in medical errors. The phenomenon has been recognised by Professor Sir Bruce Keogh, medical director of the NHS. The term "Killing Season" originated in the 1994 British medical drama series Cardiac Arrest written by Jed Mercurio (under the pseudonym John MacUre). In an episode first broadcast on BBC1 on 5 May 1994, the character Dr. Claire Maitland consoles a junior who has just committed a fatal error with the dialogue: "You come out of medical school knowing bugger all. No wonder August is the killing season. We all kill a few patients while we're learning." The day when junior doctors typically start work has also been dubbed "Black Wednesday" among NHS staff. A 2009 Imperial College London study of records for 300,000 patients at 170 hospitals between 2000 and 2008 found that death rates were 6 percent higher on Black Wednesday than the previous Wednesday. The study also found that typically fewer patients attended A&E on the first Wednesday in August than the previous week. References External links Laerdal Medical: The July Effect – Improving Patient Safety Bakhtiari, Elyas "Preparing for the July Effect: Five Strategies for Integrating New Residents, HealthLeaders Media, 7 June 2010 Patient safety Medical slang Social problems in medicine