Matthew Walker on health: what the evidence says · JRE #1109
“There is a 168% increase risk that they will get into a car accident because of the underslept state being ending a back in the same emergency room where they just came from but now is a patient.”
What the evidence says
Walker's claim echoes a real and frequently cited body of research on medical resident work hours and driving safety, but the specific 168% figure does not match the landmark study most likely being invoked. The 2005 New England Journal of Medicine study by Barger et al., based on a prospective survey of 2,737 first-year residents, found an odds ratio of 2.3 (95% CI, 1.6 to 3.3) for reporting a motor vehicle crash after an extended-duration shift compared with a non-extended shift, which corresponds to roughly a 130% increase in odds, not 168%. That same study found each extended shift scheduled in a month raised the monthly risk of a crash by about 9.1%, and raised the risk of a crash during the commute home specifically by about 16.2%. A 2024 systematic review in Cureus summarizing six studies on this topic (including the 2005 NEJM study) confirms a consistent pattern of increased crash risk, near-misses, and falling asleep at the wheel among residents after extended shifts, but none of the reviewed studies report a 168% figure. The underlying claim that extended shifts substantially raise residents' driving-accident risk is well-supported by the literature, but the specific 168% number appears to be a misstatement or misremembering of the actual reported odds ratio.