On May 7, 2020, a study of nearly 1,400 patients with moderate to severe COVID-19 disease at a single New York hospital found that patients who received the drug fared no better than patients who did not receive the drug. After using established and sophisticated statistical techniques to account for known differences between patients in the two groups, including age, sex, and initial vital signs, the researchers found that patients who received hydroxychloroquine had the same risk of intubation or death as patients who did not receive the drug The study was published online in the New England Journal of Medicine.