Understanding the Difference Between Misdiagnosis and Missed Diagnosis

While they sound similar, misdiagnosis and missed diagnosis mean very different things in a medical malpractice case.

Misdiagnosis or Missed Diagnosis?
Robert M. Marino

Robert M. Marino

April 11, 2019 09:47 AM

Misdiagnosis and missed diagnosis sound like the same thing. The two do share some key similarities. Both can lead to the needless pain and suffering of a patient. Also, both can lay the foundation for a medical malpractice lawsuit. When there is a missed diagnosis, the doctor gives the patient a clean bill of health when, in actuality, the patient is suffering from a disease or other medical condition. With a misdiagnosis situation, the doctor does in fact provide the patient with a diagnosis, but it is the wrong diagnosis. If a patient suffered as a direct result of a missed diagnosis or a misdiagnosis, they may have grounds for a medical malpractice case. Bringing a medical malpractice lawsuit can often feel like an uphill struggle. It is a complicated area of law and one rife with potential pitfalls. An attorney looking to take on a medical malpractice case must be fully aware of the difficulties that lie ahead and the amount of resources it may take to be successful.

The Difficulties in Proving Your Medical Malpractice Case

A missed diagnosis or a misdiagnosis can have catastrophic consequences for a patient. A missed diagnosis or misdiagnosis alone, however, is not enough to successfully bring a medical malpractice case. A patient must prove three important things in order to succeed in a medical malpractice case. These three things include:

  • A doctor-patient relationship existed;
  • The doctor was negligent; and
  • The doctor’s negligence caused injury to the patient.

Negligence generally comes down to whether the doctor deviated from the standard of care in evaluating the patient and arriving at a diagnosis. Medical malpractice cases involving an error in diagnosis is based on a standard set by comparing how another doctor in a similar medical specialty, under similar circumstances should have diagnosed the patient. In other words, in order to prove medical negligence, the patient must be able to show that the doctor failed to provide treatment with a level of skill and competency comparable to other professionals in the same or similar medical field.

To show negligence in a case of misdiagnosis or missed diagnosis, it is critical to understand the methodology the doctor employed in arriving at or failing to arrive at a diagnosis. Doctors use the differential diagnosis method to determine the condition of a patient. The doctor will take the patient’s history, including the patient’s complaints and symptoms, as well as a medical history. Based on that information, the doctor should perform a directed physical examination, which should lead the doctor to a list of all possible causes, ranked in order of which is most likely the case. The doctor will then perform appropriate tests and further evaluations to narrow down that list. The follow-up may include:

  • Asking more questions about symptoms
  • Performing further laboratory or radiological testing
  • Investigating the patient’s medical history
  • Referrals to specialists

In some cases, there may have been an error in one of the diagnostic tests. Whether the problem was caused due to faulty medical equipment or human error will need to be determined. Depending on the cause of the diagnostic error, the doctor may not be liable for medical malpractice. In these kinds of cases, a lab technician or other party may be responsible.

To prove that the doctor was negligent with regard to arriving at a correct diagnosis, the patient will need to show that either:

  • The doctor did not perform the differential diagnosis properly, which resulted in the missed or misdiagnosis; or
  • The doctor did not include all of the appropriate possibilities in the differential diagnosis list that a reasonably prudent physician should have considered under similar circumstances; or
  • The doctor failed to perform proper testing to rule in or rule out these possibilities and arrive at a definitive diagnosis.

Generally speaking, an expert witness will need to be called in to evaluate how the doctor employed the differential diagnosis method and whether the requisite standard of care was met.

If the patient is able to prove that the doctor was negligent, causation will still need to be addressed. Causation is another necessary, but potentially problematic, element of medical malpractice cases. It is not enough that an error in diagnosis occurred. The misdiagnosis or missed diagnosis must have directly caused harm to the patient and that, had he or she been properly diagnosed, the harm would have never occurred. Harm caused by misdiagnosis or missed diagnosis usually is due to the fact that the incorrect diagnosis led to the wrong type of medical treatment, or an absence of any treatment thus allowing the patient’s condition to get worse. The error in medical treatment may have led the patient to needlessly suffer continuing pain or it may even have caused further medical issues beyond the patient’s initial problems.

Causation can be one of the largest obstacles to overcome in a medical malpractice case. The patient must show that the suffering they endured was not just because he or she suffered from a medical condition, but that it was a direct result of the doctor’s error. The patient must show that he or she suffered in a way that would not have happened had a proper diagnosis been made. With someone already suffering a medical condition, it is necessary to show that pain was caused or exacerbated by an improper diagnosis rather than the condition itself just running its course.

Why Lawyers Don’t Take Medical Malpractice Cases

Many lawyers choose not to handle medical malpractice cases. Proof of medical malpractice can be very difficult to come by. There may be clear injuries, but then you still have to show that the injuries were a direct result of negligence. Proving causation is just one obstacle that stops attorneys from taking on medical malpractice claims. Even lawyers who choose to take on these types of cases tend to be extremely selective. This is so because medical malpractice cases are not only complicated, but require many resources in which most lawyers are not willing or able to invest. The professional liability insurers for medical professionals are prepared to defend malpractice cases with everything they have.

Not only can medical malpractice cases be intimidating to most lawyers, but they are very expensive. There are substantial upfront costs that need to be put forward to even begin investigating a potential medical malpractice case. Qualified medical experts are necessary to analyze and investigate medical records. There will be mountains of medical records and paperwork to sift through and the attorney will need to have a strong understanding of the medicine involved.

While taking on a medical malpractice case may be daunting, seeing positive results and changing the life of a client is within reach to those attorneys who have the right resources and knowledge base. The reward in successfully bringing this type of claim is helping the client achieve justice and a secure future.


Robert Marino became a lawyer because he wanted to give a voice to the voiceless. He does just that by focusing his practice on cases where people need help standing up to those who have injured them and he helps his clients protect their recoveries and benefits. His passion for the law extends to his role as an adjunct professor of law, where, for more than 15 years, he has been teaching future generations of lawyers. Rob’s practice areas include personal injury, labor law, trusts & estates, business law, medical malpractice, appellate law, and surrogate’s court.

Related Articles


Defences to a Medical Malpractice Claim


In this article PCS Law, professional discipline lawyers will share some of the defence strategies to fight a medical malpractice claim.

Person sitting beside hospital bed

Aim High and Fly

by Khalil Abdullah

From a silent victim of hometown segregation to Air Force captain and lawyer of consummate skill, Karen Evans exemplifies leadership—and vows always to help those who seek to follow her path.

Karen Evans' Leadership in the Airforce

Courtroom Mastery

by Justin Smulison

Victor H. Pribanic recalled the excitement of returning to the courtroom in late 2021 for a medical negligence case that could help set a new course for Pribanic & Pribanic’s trial advocacy.

Victor H. Pribanic Makes Return to Courtroom

New England's Best Lawyers 2022

by Best Lawyers

Our New England's Best Lawyers 2022 publication features top-ranked legal talent in New England.

New England's Best Lawyers 2022

Announcing the 2022 Best Lawyers: The Injury & Malpractice Issue

by Best Lawyers

Featuring the top legal talent from The Best Lawyers in America, Best Lawyers: Ones to Watch in America and “Lawyer of the Year” recipients for personal injury and medical malpractice as well as thought leadership from some of the nation’s top lawyers.

Best Lawyers Injury & Malpractice Publication

Georgia's Injury and Malpractice Leaders

by Justin Smulison

In 2021, Adam Malone recovered more than $38 million in settlements for catastrophically injured clients, while continuing his leadership roles outside the courtroom to enhance the profession for injury lawyers.

Malone Law Remain Leaders in Personal Injury

Georgia's Best Lawyers 2022

by Best Lawyers

Our 2022 Georgia's Best Lawyers publication features top-ranked legal talent in Atlanta, Augusta, Columbus, Greater Atlanta, Macon and Savannah.

Georgia's Best Lawyers 2022

When Medical Malpractice Defendants Are Better Able To Cope, Lawyers Are Better Able To Do Their Jobs

by Gail Fiore

Lawyers face heavy challenges when dealing with difficult medical malpractice defendants. The Winning Focus, LLC, founded by Gail Fiore, offers coaching and support to defendants feeling the burden of difficult courtroom battles.

Guidance for Medical Malpractice Defendants

Catastrophic Personal Injury

by Best Lawyers

Trial legend Frank Branson finds success mixing technology and new skills with vast courtroom experience.

Catastrophic Personal Injury

Andrew B. Yaffa - Miami 2021 Lawyer of the Year

by Best Lawyers

Medical Malpractice Law - Plaintiffs Miami, Florida

Andrew B. Yaffa

Decades of Excellence

by Justin Smulison

The powerhouse firm Lubin & Meyer continues to maintain its position of dominance in the fields of medical malpractice law and catastrophic personal injury litigation.

Lubin & Meyer Best Lawyers 2020

Tried and Tested

by Johanna Marmon

Victor Pribanic has been securing justice for wronged individuals for more than four decades.

Victor Pribanic Best Lawyers 2020

Big Wins From Coast to Coast

by Justin Smulison

Founder Michael S. Burg discusses how Burg Simpson’s lawyers secured major verdicts in some of the nation’s most unique cases in 2019.

Michael S. Burg Best Lawyers 2020

The Malone Legacy

by Alicia Lu

Adam Malone continues the legacy of improving lives he and his late father, Tommy Malone, achieved together.

Adam Malone Best Lawyers 2020

High Risks, High Rewards

by Justin Smulison

Daryl. L. Zaslow, Woodbridge, New Jersey's "Lawyer of the Year" for Medical Malpractice - Plaintiffs, discusses why he embraces high-profile injury cases.

Daryl L. Zaslow Best Lawyers 2020

No Challenge Too Big

by Justin Smulison

Following its most successful year to date, Easton & Easton continues its streak of notable victories for California’s injured.

No Challenge Too Big

Trending Articles

Announcing the 2023 The Best Lawyers in America Honorees

by Best Lawyers

Only the top 5.3% of all practicing lawyers in the U.S. were selected by their peers for inclusion in the 29th edition of The Best Lawyers in America®.

Gold strings and dots connecting to form US map

Best Lawyers: Ones to Watch in America for 2023

by Best Lawyers

The third edition of Best Lawyers: Ones to Watch in America™ highlights the legal talent of lawyers who have been in practice less than 10 years.

Three arrows made of lines and dots on blue background

The Best Lawyers in South Africa™ 2023

by Best Lawyers

Best Lawyers proudly announces lawyers recognized in South Africa for 2023.

South African flag

Could Reign Supreme End with the Queen?

by Sara Collin

Canada is revisiting the notion of abolishing the monarchy after Queen Elizabeth II’s passing, but many Canadians and lawmakers are questioning if Canada could, should and would follow through.

Teacup on saucer over image of Queen's eye

Famous Songs Unprotected by Copyright Could Mean Royalties for Some

by Michael B. Fein

A guide to navigating copyright claims on famous songs.

Can I Sing "Happy Birthday" in Public?


2022: Another Banner Year

by John Fields

Block O’Toole & Murphy continues to secure some of New York’s highest results for personal injury matters.

Three men in business suits standing in office

Announcing the 2023 The Best Lawyers in Canada Honorees

by Best Lawyers

The Best Lawyers in Canada™ is entering its 17th edition for 2023. We highlight the elite lawyers awarded this year.

Red map of Canada with white lines and dots

Wage and Overtime Laws for Truck Drivers

by Greg Mansell

For truck drivers nationwide, underpayment and overtime violations are just the beginning of a long list of problems. Below we explore the wages you are entitled to but may not be receiving.

Truck Driver Wage and Overtime Laws in the US

What the Courts Say About Recording in the Classroom

by Christina Henagen Peer and Peter Zawadski

Students and parents are increasingly asking to use audio devices to record what's being said in the classroom. But is it legal? A recent ruling offer gives the answer to a question confusing parents and administrators alike.

Is It Legal for Students to Record Teachers?

The Upcycle Conundrum

by Karen Kreider Gaunt

Laudable or litigious? What you need to know about potential copyright and trademark infringement when repurposing products.

Repurposed Products and Copyright Infringemen

Thirteen Years of Excellence

by Best Lawyers

For the 13th consecutive year, “Best Law Firms” has awarded the most elite and talented law firms across the country through a thorough and trusted data review process.

Red, white and blue pipes and writing on black background

Caffeine Overload and DUI Tests

by Daniel Taylor

While it might come as a surprise, the over-consumption of caffeine could trigger a false positive on a breathalyzer test.

Can Caffeine Cause You to Fail DUI Test?

Choosing a Title Company: What a Seller Should Expect

by Roy D. Oppenheim

When it comes to choosing a title company, how much power exactly does a seller have?

Choosing the Title Company As Seller

Announcing the 2022 Best Lawyers® in the United States

by Best Lawyers

The results include an elite field of top lawyers listed in the 28th Edition of The Best Lawyers in America® and in the 2nd Edition of Best Lawyers: Ones to Watch in America for 2022.

2022 Best Lawyers Listings for United States

Announcing The Best Lawyers in Australia™ 2023

by Best Lawyers

The results include an elite field of top lawyers and firms from Australia.

The Best Lawyers in Australia™ 2023

Announcing The Best Lawyers in Germany™ 2023

by Best Lawyers

The results include an elite field of top lawyers and firms from Germany.

Black, red and yellow stripes