Do Not Go to the Hospital in July

Month to month, over the last several decades, deaths attributable to errors in the amounts and/or types of medicines prescribed or administered at hospitals have varied little. Except during July, when the rate spikes roughly 10 percent, the new study finds. And the likely reason: green doctors. This month-long blip just happens to correspond to when newly minted medical residents are released into teaching hospitals with substantial autonomy to make medical decisions, explain David Phillips and Gwendolyn Barker of the University of California at San Diego.

Owing to their “new resident hypothesis,” they examined death rates for medication errors by county, accounting for the share of teaching hospitals in each. And, they now report, “the greater the concentration of teaching hospitals in a region, the greater the July Effect for . . . [fatal] medication errors.” Indeed, the 10 percent spike disappeared when the new analysis looked only at areas without teaching hospitals.