Medical errors as extreme as operating on the wrong body part or the wrong patient are never supposed to happen. Systematic efforts to eliminate these "never events" began a decade ago, and yet such errors continue regularly in Oregon and across the U.S. The most thorough national study estimated 1,300 to 2,700 people are harmed every year by wrong site errors. The frequency in Oregon appears unchanged since the state began voluntary error reporting in 2006, when hospitals listed eight wrong site or wrong patient errors. In each of the past two years, Oregon hospitals reported 10 wrong site, wrong patient, or wrong procedure errors, one resulting in a patient death. Since reporting to the Oregon Patient Safety Commission is voluntary, it's only a rough indicator of the numbers. Researchers have found that it's very easy for surgeons to confuse left and right when standing over rather than facing a patient. For some procedures, such as spinal surgery, target sites are hard to distinguish from healthy sites. Identical or similar patient names cause mix-ups.