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The Chiropractic Impact Report

Courtesy Of Dr. John Doe

January 2024

Safety of Mechanical Care

People become healthcare providers because they are interested, often passionately, about helping others with their health. Most healthcare providers are horrified at the thought that anything they did or failed to do could end up harming a patient. Yet, every type of health care is associated with some risks of potential problems. These problems can range from an annoyance to soreness to disability or even to death.

In acknowledging the existence of risks or problems associated with healthcare interventions, healthcare licensing bodies, governments, and associations have established “standards of care” for each healthcare discipline. These “standards of care” include informing patients about known or statistical risks/complications/harms that have been documented to occur following the healthcare intervention that is being proposed.

For decades, top universities and top medical journals have been documenting errors and the consequences of those errors that occur as a consequence of traditional medical healthcare in the United States. These studies often emphasize the hospital setting where such errors are more easily quantified. Sadly, the early data is scary. It comes with warnings about how improvements are imperative. Yet, recent data (2023) shows that not much progress, if any, has been made.


In 1994, the Journal of the American Medical Association published an article titled (1):

Error in Medicine

 The author, Lucian Leape, MD, is from the Harvard School of Public Health. This study only looked at hospital error. Dr. Leape notes and cites:

  • A 1964 study reported that 20% of patients admitted to a university hospital medical service suffered iatrogenic injury and that 20% of those injuries were serious or fatal. [Annals of Internal Medicine]
  • A 1981 study found that 36% of patients admitted to a university medical service in a teaching hospital suffered an iatrogenic event, of which 25% were serious or life threatening. More than half of the injuries were related to use of medication. [New England Journal of Medicine]
  • A 1991 study found that 64% of cardiac arrests at a teaching hospital were preventable and that inappropriate use of drugs was the leading cause of the cardiac arrests. [Journal of the American Medical Association]
  • A 1991 study of hospitalized patients from New York found that 4% suffered an injury that prolonged their hospital stay or resulted in measurable disability. [New England Journal of Medicine]

Dr. Leape notes that if the data from these studies were applied to the entire U.S. population, “180,000 people die each year as a result of iatrogenic injury, the equivalent of three jumbo jet crashes every 2 days.” Dr. Leape states:

“For years, medical and nursing students have been taught Florence Nightingale’s dictum—first, do no harm.”

“Yet, evidence from a number of sources, reported over decades, indicates that a substantial number of patients suffer treatment-caused injuries while in the hospital.”

“Autopsy studies have shown high rates (35% to 40%) of missed diagnoses causing death.”


In 1998, the Journal of the American Medical Association published a study titled (2):

Incidence of Adverse Drug Reactions in Hospitalized Patients
A Meta-analysis of Prospective Studies

The authors of this study were from the University of Toronto. Their study evaluated 39 prospective studies from U.S. hospitals. The authors defined serious Adverse Drug Reactions (ADRs) as:

“Serious ADRs were defined as those that required hospitalization, were permanently disabling, or resulted in death.”


  • The authors “excluded errors in drug administration, noncompliance, overdose, drug abuse, therapeutic failures, and possible ADRs.”
  • The authors investigated “injuries incurred by drugs that were properly prescribed and administered.”
  • “Possible ADRs” were excluded from this study.


The authors found that, overall, 2,216,000 U.S. hospitalized patients had serious ADRs and 106,000 had fatal ADRs, making these reactions between the fourth and sixth leading cause of death yearly in the United States.

Comments by the Authors:

“The incidence of serious and fatal ADRs in US hospitals was found to be extremely high.”

“We have found that serious ADRs are frequent and more so than generally recognized.”

“Their [fatal ADRs] incidence has remained stable over the last 30 years.”

“[This study on ADRs, which excluded medication errors, showed] that there are a large number of serious ADRs even when the drugs are properly prescribed and administered.”

“The costs associated with ADRs may be very high.”

“It is important to note that we have taken a conservative approach, and this keeps the ADR estimates low by excluding errors in administration, overdose, drug abuse, therapeutic failures, and possible ADRs. Hence, we are probably not overestimating the incidence of ADRs.”

A critical understanding from the data in this study is that it only assessed patients in the hospital. Problems outside of the hospital, such as outpatient care, long-term care centers, home, etc. were not included. Yet, the average of 106,000 hospitalized patients died and 2,216,000 had a serious reaction to the right drug being given for the correct diagnosis and in the correct dose, yearly.


In 1999, an editorial was published in the British Medical Journal (BMJ), titled (3):

Reducing Errors in Medicine:
It’s Time to Take this More Seriously

Drs. Berwick and Leape make this analogy:

“Ladies and gentlemen, welcome aboard Sterling Airline’s Flight Number 743, bound for Edinburgh. This is your captain speaking. Our flight time will be two hours, and I am pleased to report both that you have a 97% chance of reaching your destination without being significantly injured during the flight and that our chances of making a serious error during the flight, whether you are injured or not, is only 6.7%. Please fasten your seatbelts, and enjoy the flight. The weather in Edinburgh is sunny.”

“Would you stay aboard? We doubt it.”

“In health care it is a totally different story. With the rising complexity and reach of modern medicine have come startling levels of risk and harm to patients. One recent study in two of the most highly regarded hospitals in the world discovered serious or potentially serious medication errors in the care of 6.7 out of every 100 patients, and the Harvard Medical Practice Study, which reviewed over 30,000 hospital records in New York state, found injuries from care itself (‘adverse events’) to occur in 3.7% of hospital admissions, over half of which were preventable and 13.6% of which led to death. If these figures can be extrapolated to American health care in general then over 120,000 Americans die each year as a result of preventable errors in their hospital care.”

“Studies in Australia, Israel, the United Kingdom and elsewhere, suggest levels of error and hazard in patient care that are no lower than in America.”


In 1999, the lay press printed a study titled (4):

HMO Chief: Patients are at Risk:
Blunders take 400,000 Lives Every Year, Kaiser Head Says

This publication quotes Dr. David Lawrence, who was chief executive of Kaiser Permanente, in a speech to the national Press Club. Kaiser is the U.S.’s largest HMO. Dr. Lawrence states:

“Medical accidents and mistakes kill 400,000 people a year, ranking behind only heart disease and cancer as the leading cause of death.” 

“Mistakes alone kill more people each year than tobacco, alcohol, firearms, or automobiles.”

“[Patients] continue to believe in the myth of Marcus Welby, the unbridled benefits of technology and the assumption that competence and safety are spread evenly and consistently throughout the health care system.”

“If passengers were asked to fly with a commercial airline organized like most health care, they wouldn’t get on the plane.”


In 2000, a study was published in the Journal of the American Medical Association titled (5):

Is US Health Really the Best in the World?

The author, Barbara Starfield, MD, MPH, is from Johns Hopkins School of Hygiene and Public Health.

Dr. Starfield notes that there is accumulating information concerning the deficiencies of US medical care; 20% to 30% of patients receive contraindicated care.  The US ranks behind Japan, Sweden, Canada, France, Australia, Spain, Finland, the Netherlands, the United Kingdom, Denmark, and Belgium.

The U.S. health care system itself appears to be linked to “poor health through its adverse effects.” For example, Dr. Starfield cites:

  • 7,000 deaths/year from medication errors in hospitals
  • 12,000 deaths/year from unnecessary surgery
  • 20,000 deaths/year from other errors in hospitals
  • 80,000 deaths/year from nosocomial infections in hospitals
  • 106,000 deaths/year from non-error, adverse effects of medications

These total to 225,000 deaths per year from iatrogenic causes. These estimates are for deaths only and do not include adverse effects that are associated with disability or discomfort. If other estimates are used, the deaths due to iatrogenic causes would range from 230,000 to 284,000. Dr. Starfield states:

“In any case, 225,000 deaths per year constitutes the third leading cause of death in the United States, after deaths from heart disease and cancer.”

“Recognition of the harmful effects of health care interventions, and the likely possibility that they account for a substantial proportion of the excess deaths in the United States compared with other comparably industrialized nations, sheds new light on imperatives for research and health policy.”  

“The US population does not have anywhere near the best health in the world. Of 13 countries in a recent comparison, the United States ranks an average of 12th (second from the bottom) for 16 available health indicators.”


In 2009, a study published in the Journal of the American Medical Association titled (6):

Exploring the Harmful Effects of Health Care

The authors Charles M. Kilo, MD, MPH and Eric B. Larson, MD, MPH, were from The Trust for Healthcare Excellence in Portland, OR.

These authors are quite cynical, suggesting that the benefits of the U.S. healthcare system may not outweigh the harms that it causes. There is evidence that about one-third of medical spending is for services that do not improve health or the quality-of-care, and may make things worse. The U.S. healthcare delivery can cause direct adverse physical and emotional effects. The authors state:

“Although health care’s objective should be to improve health, its primary emphasis has been on producing services.”

“The benefits that US health care currently deliver may not outweigh the aggregate health harm it imparts.”

“Higher-intensity care generally does not improve survival, and complications of medical care accounted for 1.1 million hospitalizations in 2006, costing nearly $42 billion.”

“Exaggerated fears and ‘medicalizing’ normal phenomena are as harmful as unrealistic expectations and are fostered frequently by marketing hype and sometimes inadvertently by health care clinicians.”

“The possibility that health care might cause net harm is increasingly important given the sheer magnitude of the modern health care enterprise.”


 In 2011, a study was published in the journal Health Affairs titled (7):

‘Global Trigger Tool’ Shows That Adverse Events in Hospitals
May Be Ten Times Greater Than Previously Measured

The authors, from the University of Utah, explore the best method for estimating the incidence of adverse events in hospitals so that patient safety outcomes against such events can be optimized. They found that the adverse event detection methods commonly used to track patient safety in the United States fared very poorly compared to other methods and missed 90% of the adverse events.

Overall, the authors found that adverse events occurred in one-third of hospital admissions. Because some admissions suffered from more than one adverse event, the rate of adverse events rose to essentially half of admissions. The authors state:

“Our study suggests that despite sizable investments and aggressive promotional efforts by local hospitals, these reporting systems fail to detect most adverse events.”

“Our study also detected far more adverse events in hospitalized patients than have been found in prior studies.”

“Despite more than a decade of focus on improving patient safety in the United States, the current rates of adverse events among inpatients at three leading hospitals are still quite high at 33.2 percent of hospital admissions for adults.”

“The true rates are likely to be higher still, given the consistent finding that direct observational studies reveal higher rates of adverse events than retrospective studies because not all adverse events are documented in the patient record.”

“Our findings indicate that two methods commonly used by most care delivery organizations and supported by policy makers to measure the safety of care—enhanced voluntary reporting systems and the use of the Agency for Healthcare Research and Quality’s Patient Safety Indicators—fail to detect more than 90 percent of the adverse events that occur among hospitalized patients.” 

“Despite almost ten years since the Institute of Medicine report on patient safety, rates of adverse events in hospital patients are still high.” 


In 2016, an article was published in the British Medical Journal (BMJ) titled (8):

Medical Error:
The Third Leading Cause of Death in the United States

The authors are from the Department of Surgery, Johns Hopkins University School of Medicine. They analyzed the scientific literature on medical error to identify its contribution to U.S. deaths. Their primary concern  is that “medical error is not included on death certificates or in rankings of cause of death.” The annual list of the most common causes of death in the United States, compiled by the Centers for Disease Control and Prevention (CDC), has a major limitation as it relies on assigning an International Classification of Disease (ICD) code to the cause of death, and ICD code does not include error. The authors state:

“Currently, deaths caused by [medical] errors are unmeasured.”

“If medical error was a disease, it would rank as the third leading cause of death in the US.”

“Medical error is the third biggest cause of death in the US and therefore requires greater attention.”

“Medical error leading to patient death is under-recognized in many other countries, including the UK and Canada.” 

“The system for measuring national vital statistics should be revised to facilitate better understanding of deaths due to medical care.”


In 2023, an article was published in the BMJ (British Medical Journal) Quality & Safety, titled (9):

Burden of Serious Harms from Diagnostic Error in the USA

The authors are from Johns Hopkins School of Medicine and Harvard Medical School. The goal of this research was to estimate the total number of serious misdiagnosis-related harms (i.e., permanent disability or death) occurring annually in the USA across all care settings (ambulatory clinic, emergency department, and inpatient). This is the first national estimate of permanent morbidity and mortality resulting from diagnostic errors across all clinical settings, including both hospital-based and clinic-based care each year in the USA alone. Importantly, this study, “considered only false negative diagnoses (i.e., initially missed or delayed) and associated harms.” The authors note:

“Diagnostic errors cause substantial preventable harms worldwide.”

“An estimated 795,000 Americans become permanently disabled or die annually across care settings because dangerous diseases are misdiagnosed.”

“This manuscript provides the first robust, national annual US estimate for serious misdiagnosis-related harms (nearly 800,000 combined deaths (~371,000) or permanent disabilities (~424,000)) across care settings (ambulatory clinic, emergency department, and inpatient).”

“Across clinical settings (ambulatory clinics, emergency department, and inpatient), we estimate that nearly 800,000 Americans die or are permanently disabled by diagnostic error each year, making it the single largest source of serious harms from medical mistakes.” 

“The number of affected patients is large, and this makes diagnostic error a pressing public health concern.”

“Total annual diagnostic errors in the USA likely number in the tens of millions.”

“Measured error and harm rates in primary care and emergency departments are similar in the USA, the UK, and Western Europe.”

Chiropractic Care

In 2022, a study was published in the journal Healthcare, and titled (10):

Safety of Chuna Manipulation Therapy in 289,953 Patients
with Musculoskeletal Disorders

This study was from medical facilities in South Korea. It involved a form of high-velocity low amplitude spinal adjustment (specific line-of-drive manipulation). This type of traditional joint manipulation is similar to that in chiropractic. This type of manual therapy has been incorporated into the Korean health care system and has been administered in 16.4% of inpatients and 83.6% of outpatients with musculoskeletal disorders in Korean medicine hospitals specializing in spine and joint diseases.

The authors make these observations:

“Manual therapy is performed in various forms by chiropractors, osteopaths, and physical therapists across the world, including the United States, Europe, and Australia.”

“The use of spinal manipulation has increased in recent decades in Western countries, as has the popularity of chiropractic therapy among American adults.”

“The UK National Institute for Health and Clinical Excellence guidelines now recommend manual therapy for treating persistent or subacute lower back pain.”

This study was also massive. In total, the authors assessed 2,682,258 manipulation procedures that were performed on 289,953 patients from 14 different facilities. The authors state:

“In this study, 289,953 patients and more than 2.5 million cases of CMT were reviewed, making it a rare, very wide-ranging, and reliable investigation of severe adverse events.”

Adverse events were graded as follows:

MILD: asymptomatic or mild symptoms

MODERATE: minimal, local, or non-invasive intervention indicated

SEVERE: severe or medically significant but not immediately life-threatening; hospitalization or prolongation of hospitalization indicated

LIFE-THREATENING: urgent intervention indicated

FATAL: death

The authors state:

“Our analysis of 289,953 patients and 2,682,258 cases of CMT indicates that both mild–moderate and severe AEs are rare after CMT.”

“Adverse events of any level of severity were very rare after CMT.”

“There were no instances of carotid artery dissection or spinal cord injury.”

No life-threatening or fatal events were identified. Eleven rib fractures were noted on elderly patients with osteoporosis, but all recovered without residuals.


In 2023, a study was published in the journal Scientific Reports, and titled (11):

A Retrospective Analysis of the Incidence of Severe Adverse Events Among Recipients of Chiropractic Spinal Manipulative Therapy

This study examined the incidence and severity of adverse events (AEs) in 54,846 patients who received 960,140 chiropractic spinal manipulations. Data originated from 30 chiropractic clinics using 38 different chiropractors. All patients received spinal manipulative therapy (SMT) administered via manual thrust (i.e., a hands-on impulse applied to the spinal joints). The authors concluded:

“In this study, severe spinal manipulative therapy-related adverse events were reassuringly very rare.”

“There were no adverse events related to stroke or cauda equina syndrome.” 

“There were no cases of stroke, transient ischemic attack, vertebral or carotid artery dissection, cauda equina syndrome, or spinal fracture.”

“No adverse events were identified that were life-threatening or resulted in death.”

“No adverse events were reported to be permanent.”

Once again, two rib fractures were identified, both occurring in elderly patients with a history of osteoporosis. Both patients recovered without residuals.


Chiropractic care is in a unique position. These last two robust studies document the extreme safety of chiropractic care. When a patient fails to respond to chiropractic care, medical referral is standardly done by chiropractors with the intention of benefiting the patient with the best of both approaches to healthcare. Often the chiropractic input is invaluable in helping to reduce missed diagnoses.


  1. Leape L; Error in Medicine; Journal of the American Medical Association; December 21, 1994; Vol. 272; No. 23; pp. 1851-1857.
  2. Lazarou, BH Pomeranz BH, PN Corey PN: Incidence of Adverse Drug Reactions in Hospitalized Patients: A Meta-analysis of Prospective Studies; Journal American Medical Association; April 15, 1998; Vol. 279; No. 15; pp. 1200-1205.
  3. Berwick D, Lucian L; Reducing Errors in Medicine; It’s Time to Take this More Seriously; British Medical Journal (BMJ); July 17, 1999; Vol. 318; pp. 136-137.
  4. Rosenblatt RA; “HMO Chief: Patients are at risk: Blunders take 400,000 lives every year, Kaiser head says;” LOS ANGELES TIMES, Oakland Tribune; July 15, 1999.
  5. Starfield B; Is US Health Really the Best in the World?; Journal of the American Medical Association; July 26, 2000; Vol. 284; No. 4; pp. 483-485.
  6. Kilo KM, Larson EB; Exploring the Harmful Effects of Health Care; Journal of the American Medical Association; July 1, 2009; Vol. 302; No. 1; pp. 89-91.
  7. Classen DC, Resar R, Griffin F, Federico F, Frankel T, Kimmel N, Whittington JC, Frankel A, Seger A, James BC; ‘Global Trigger Tool’ Shows That Adverse Events in Hospitals May Be Ten Times Greater Than Previously Measured; Health Affairs; April 2011; Vol. 30; No. 4; pp. 581-589.
  8. Makary MA; Medical Error: The Third Leading Cause of Death in the United States; British Medical Journal (BMJ); May 3, 2016; Vol. 353; Article i2139.
  9. Newman-Toker DE, Nassery N, Schaffer AC, Yu-Moe CW, Clemens GD, Wang Z, Zhu Y, Tehrani SAS, Fanai M, Hassoon A, Siegal D; Burden of Serious Harms from Diagnostic Error in the USA; BMJ [British Medical Journal] Quality & Safety; July 17, 2023; Epub [accessed December 6, 2023]
  10. Kim S, Kim G, Kim H, Park J, Lee J, and nine more; Safety of Chuna Manipulation Therapy in 289,953 Patients with Musculoskeletal Disorders: A Retrospective Study; Healthcare; February 2, 2022; Vol. 10; No. 2; Article 294.
  11. Chu E, Trager RJ, Lee L, Niazi IK; A Retrospective Analysis of the Incidence of Severe Adverse Events Among Recipients of Chiropractic Spinal Manipulative Therapy; Scientific Reports; January 23, 2023; Vol. 13; No. 1; Article 1254.

“Authored by Dan Murphy, D.C.. Published by ChiroTrust® – This publication is not meant to offer treatment advice or protocols. Cited material is not necessarily the opinion of the author or publisher.”