Medical errors may now be the third leading cause of death in the US. Researchers at Johns Hopkins University estimate that 251,000 deaths a year are the result of medical mistakes – and they are calling for better reporting nationwide, in order to understand the scale of the problem. Researchers say that deaths caused by medical error are hard to track because of the international coding system that is currently used on death certificates. The study is published in the latest edition of BMJ, the Medical Journal. Its authors hope their analysis will lead to healthcare reforms and better patient safety measures.