Medical error is the third leading cause of death in the US.

Medical error has been defined as an unintended act (either of omission or commission) or one that does not achieve its intended outcome. Patient harm from medical error can occur at the individual or system level.

Makary M A, Daniel M. Medical error—the third leading cause of death in the US. BMJ 2016; 353 :i2139 doi:10.1136/bmj.i2139