The claim that medical error is the third leading cause of death, and the paper that called it very likely wrong
A 2016 BMJ analysis put deaths from medical error at 251,454 a year. The next year, in BMJ Quality and Safety: "the new estimate is very likely to be wrong". Studies that judge deaths one by one find 1 to 3.6 percent preventable.
We have not finished checking this source. No judgement either way. how we score evidence
Caveat on this rating: This row is the contest. The 251,454 is an arithmetic average of four earlier estimates, one from a for-profit ratings company, resting on studies with 14 or fewer deaths each; the 25,000 is a different extrapolation from a 3.6 percent preventability rate. Neither is a count. What is not contested: the death certificate does miss human and system factors, care does harm people far more often than reporting systems admit, and the two sides disagree about the size of the death toll, not about whether error kills.
In 2016 two Johns Hopkins surgeons argued in the BMJ that medical error kills 251,454 Americans a year, which would rank it third after heart disease and cancer. The number went everywhere. It is contested, and this stop carries both sides.
The claim
Their point about the death certificate is sound: the CDC's cause-of-death list is built from ICD codes, and "causes of death not associated with an ICD code, such as human and system factors, are not captured". They wrote: "We focus on preventable lethal events to highlight the scale of potential for improvement."
The critique
The following year, in the BMJ's own patient-safety journal, Shojania and Dixon-Woods took it apart. "We propose that the new estimate is very likely to be wrong." "The new paper is not a study." The authors "simply took the arithmetic average of four estimates", one of them from HealthGrades, "a for-profit company that markets quality and safety ratings". The studies underneath were designed to count harms, not deaths, and contained almost none: 14 deaths in the North Carolina study (0.6 percent of patients), 3 and 12 in two government reports, 9 in another. "Any extrapolation that generalises from so few deaths (14 or fewer) to so many (200 000-400 000) surely warrants substantial scepticism."
Studies built to do the one thing that matters here, to look at each inpatient death and ask whether it was avoidable, find "proportions under 5%, typically in the range of 1%-3%"; the largest found 3.6 percent. "Around 700 000 deaths occur in US hospitals annually." At 3.6 percent, "something like 25 000 deaths might be averted each year by eliminating medical error, a far cry from 251 454."
What neither side settles
The critics' 25,000 is also an extrapolation, from a different country's hospitals, and "preventable" judged after the fact by a reviewer is its own kind of soft number. The honest answer is that nobody has a defensible national count. The range of published estimates runs from about 25,000 to about 400,000, and the difference is what each one counts: injuries from care scaled up, or deaths judged preventable one at a time. Patients who suffer a hospital-acquired complication were also the most likely to die anyway; "many patients die with, rather than of, these conditions."
Worth asking
When a number this large is quoted to you, ask whether it came from a study or from an average of other people's estimates.
Source
Medical error: the third leading cause of death in the US — Makary MA, Daniel M (2016)
Read the source: https://doi.org/10.1136/bmj.i2139
DOI: 10.1136/bmj.i2139
How this was scored
- Study design
- not recorded
- Funding
- not recorded
- Published in
- not recorded
- Sample size
- not recorded
- Preregistered
- not recorded
- Conflicts disclosed
- not recorded
- Independent of proponent
- not recorded
- Retracted
- No
We have not finished checking this source, so there is no scoring to show yet. “We have not checked this yet” and “this is disputed” are different statements, so no scored band is shown rather than a low one.
Read the full scoring rubric, including what it can't tell you.
Published September 29, 2026.
Questions
How strong is the evidence behind this?
veisund rates this source "not yet assessed". We have not finished checking this source. No judgement either way. One caveat travels with that badge: This row is the contest. The 251,454 is an arithmetic average of four earlier estimates, one from a for-profit ratings company, resting on studies with 14 or fewer deaths each; the 25,000 is a different extrapolation from a 3.6 percent preventability rate. Neither is a count. What is not contested: the death certificate does miss human and system factors, care does harm people far more often than reporting systems admit, and the two sides disagree about the size of the death toll, not about whether error kills. The score is calculated from recorded facts about the source — study design, funding, publication venue, sample size, preregistration — not typed in by an editor.
What is the source for this?
Medical error: the third leading cause of death in the US — Makary MA, Daniel M (2016). DOI: 10.1136/bmj.i2139. The full source is linked on this page so you can read it yourself.
Is this medical advice?
This is information to bring to your prescriber, not medical advice and not a reason to change anything on your own. Nothing here is an instruction to stop or reduce a medication. If you are in crisis, call or text 988.
This is information to bring to your prescriber, not medical advice and not a reason to change anything on your own. Nothing here is an instruction to stop or reduce a medication. If you are in crisis, call or text 988.