From John Hopkins website - 2016:

SHARE FAST FACTS *10 percent of all U.S. deaths are now due to medical error. *Third highest cause of death in the U.S. is medical error *Medical errors are an under-recognized cause of death

"Analyzing medical death rate data over an eight-year period, Johns Hopkins patient safety experts have calculated that more than 250,000 deaths per year are due to medical error in the U.S"

https://www.hopkinsmedicine.org/news/media/releases/study_suggests_medical_errors_now_third_leading_cause_of_death_in_the_us

Good book to get: "Unaccountable: What Hospitals Won’t Tell You and How Transparency Can Revolutionize Health Care" by Marty Makary (Bloomsbury Press, 2012).