The CDC keeps tabs on the most common causes of death for educational and research purposes.

This list is compiled using International Classification of Disease (ICD) code data from physicians, funeral directors, coroners, and medical examiners.

The top 2 causes—heart disease and cancer—accounted for nearly half (46.1%) of all deaths in 2013, and they affect a higher percentage of men than women, according to the CDC.

Although the CDC cites the third most common cause of death as chronic lower respiratory diseases, a recent analysis published in BMJ argues that it’s actually medical errors.

Johns Hopkins University School of Medicine professor Martin Makary and research fellow Michael Daniel noted that the CDC’s list is limited by ICD codes, which must be assigned as the cause of death. Currently, there’s no ICD code for human and system factors, the authors pointed out.

They defined medical error as “an unintended act (either of omission or commission) or one that does not achieve its intended outcome, the failure of a planned action to be completed as intended (an error of execution), the use of a wrong plan to achieve an aim (an error of planning), or a deviation from the process of care that may or may not cause harm to the patient.”

They provided this case history of a medical error as an example:

A young woman recovered well after a successful transplant operation. However, she was readmitted for nonspecific complaints that were evaluated with extensive tests, some of which were unnecessary, including a pericardiocentesis. She was discharged but came back to the hospital days later with intra-abdominal hemorrhage and cardiopulmonary arrest. An autopsy revealed that the needle inserted during the pericardiocentesis grazed the liver, causing a pseudoaneurysm that resulted in subsequent rupture and death. The death certificate listed the cause of death as cardiovascular.

One 1999 report from the Institute of Medicine (IOM) estimated the number of deaths due to medical errors at somewhere between 44,000 and 98,000 annually. Another report published in 2004 suggested that there were around 195,000 medical error-related deaths per year.

Meanwhile, the US Department of Health and Human Services’ Office of the Inspector General uncovered 180,000 annual deaths due to medical errors among Medicare beneficiaries in 2008, and another study suggested that the rate was around 1.13%.

“If this rate is applied to all registered US hospital admissions in 2013, it translates to over 400,000 deaths a year—more than 4 times the IOM estimate,” the authors wrote, noting that none of the studies accounted for deaths outside of inpatient care, such as care at home, in nursing homes, or in ambulatory surgery centers.

The authors acknowledged that their extrapolation of study data to a broader US population is a study limitation, but they argued that the lack of data shows a need for better recording of the issue.

They offered 3 ways to help prevent and address medical errors:

1.      Make errors more visible when they happen, so that the problem can be addressed quickly.

2.      Have solutions on-hand to help patients when the incident occurs.  

3.      Prevent errors by taking into account health care providers’ limitations.

They also suggested that death certificates could have an open field to detail whether a “preventable complication stemming from the patient’s medical care contributed to the death.”

“More appropriate recognition of the role of medical error in patient death could heighten awareness and guide both collaborations and capital investments in research and prevention,” the authors wrote.

In addition to heart disease, cancer, chronic lower respiratory diseases, and (arguably) medical errors, the next most common causes of death are accidents, stroke, Alzheimer’s disease, diabetes, influenza and pneumonia, nephritis/nephrosis, and suicide, according to the CDC.