By Stephen Broomes MD

Diagnostic errors are a failure to provide an accurate and timely explanation of the patient’s health problems or communicate that explanation to the patient (World Health Organization).

Scope of the problem: Diagnostic errors affect an estimated 12 million Americans, and likely cause more harm to patients than all other medical errors combined. An estimated 40,000 to 80,000 people die each year from diagnostic failures in U.S. hospitals alone, and probably at least that many suffer permanent disability. The total across all clinical settings is likely much higher.[1]

According to the American College of Physicians:
“More than 100,000 U.S. medical liability cases over the past 3 decades involved diagnostic errors, according to a recent study by Dr. Newman-Toker and colleagues. These cases represented 29% of all those included in the U.S. National Practitioner Data Bank, making diagnostic mistakes the leading cause of medical liability claims, they reported in the August BMJ Quality & Safety. The average, inflation-adjusted payout in these cases was nearly $400,000—higher than for any other kind of medical mistake.”

Medical Malpratice Carrier
The following data is from The Doctors (physician-owned malpractce insurance carrier) after reviewing their cases for an unspecified year. They found that out of 350 hospital-based Internal Medicine claims that 118 of them were related to diagnostic errors and fell into the following categories of diseases:

1. Acute CVA (stroke) 8.5%
2. Acute MI (heart attack) 5.0%
3. Pulmonary Embolism (blood clots in the lungs) 4.2%
4. Spinal Epidural Abscess (infection surrounding the spinal cord) 4.2%
5. Lung Cancer 3.4%

Facts that Lead to Diagnostic Errors
There are many factors that also contribute to the clinician generating an improper differential diagnosis that are not in their control. The following is a list of those factors and have been under ongoing investigation by a conglomerate of clinicians (and funded with millions of dollars for a three-year study:

1. Incomplete communication during care transitions

  •  This refers to an accepting physician not requesting or receiving the correct information about a patient at a point in their hospitalization that allows the receiving physician to generate a differential diagnosis from their position. This is a major factor leading to harm and is a major initiative in major medical systems across the country

2. Lack of measures and feedback

  • In order for physicians to grow professionally, they need consistent feedback about key performance indicators. If they do not receive this feedback it is extremely difficult to improve their diagnostic skills

3. Limited support to help with clinical reasoning

  • This is achieved by providing physicians with readily available resources with which they may improve their understanding of diagnostic options at the point of care

4. Limited time

  • All physicians are under more pressure to care for ever-increasing volumes of patients in hospital settings. This can lead to fatigue and cluttered thought processes which will inevitably lead to missed diagnoses

Case Study #1
An 18 year old with a history of childhood seizures and headache was transferred from her OB/GYNs office to the emergency room complaining of abdominal pain and mild headache. During the visit in the doctor’s office she had a syncopal episode that was interpreted as a seizure. In the emergency room she had a complete work up including a Cat scan of the head that was unrevealing. She had no laboratory abnormalities, fever, neck stiffness, or photophobia. She remained in the hospital and had intermittent headaches that were responsive to mild pain medications and generalized malaise. The ongoing workup was negative. The patient never developed any identified physical, vital sign, or lab abnormalities despite being evaluated by multiple specialists. At some point because the workup was negative and because the patient was continuously symptomatic a lumbar puncture was performed. At that point it was noted that her intracranial pressure was extremely high and her culture grew an extremely rare fungal organism that is usually only found in HIV patients despite the fact that the patient had no medical problems. The CDC was contacted and a case report was published. The patient expired after being transferred to a tertiary care center.

Case Study #2
An 87 year-old female was brought to the emergency room on 1/23/15 due to chest pain. A review of the patient’s medical records indicated that she was having right-sided chest pain with radiation to the right arm and jaw starting on 1/19/15. The pain eventually worsened on the night prior to admission, and the family subsequently called EMS. Upon arrival at the hospital, patient’s blood pressure was 200/100. An EKG was performed in the ambulance which revealed ST segment elevations in leads V2-V4. A review of the medical records from the hospital indicates that the actual EKG strip obtained by EMS was not documented as having been visualized by the attending physicians or other assisting physicians in the ER. An EKG performed in the ER showed a septal infarct and anterolateral ischemia but no ST elevation. This created inconsistencies in the medical documentation and lead to a missed opportunity to correctly identify a medical condition and the patient suffered additional myocardial infarction that was due to a near total occlusion of the left main coronary artery. The patient ultimately succumbed.

Case Study #3
A patient was admitted to the hospital due to nausea and vomiting and was diagnosed as a case of acute gastroenteritis. A nurse’s note documents that the patient complained of back pain graded as 8 out of 10. It was also noted that she was able to move all extremities during the encounter. Meanwhile, the Braden-Scale Sensory Adult Perception at the time was 15-18 (Mild). In the assessment, it was recorded that the patient had no sensory deficit, made frequent and major position changes, no mobility limitations, and walks occasionally during the day but with shorter distances. The patient continued to experience severe weakness throughout the hospitalization which contradicted the neurologic exam detailed by the admitting physician and the admitting notes that seem to indicate that she was able to move all of her extremities and that her Braden Scale was only mildly diminished. The patient was seen by the doctor and the notes reflect a clear concern for the complaints of lower extremity weakness being out of proportion to the upper extremity. During the same day patient’s blood cultures grew MSSA and urine cultures grew Klebsiella. No clear differential diagnosis for the MSSA results were developed. Over the course of the ensuing days the patient began displaying more and more objective evidence of spinal cord pathology and infection as documented by the doctor in his progress notes. There was a period of approximately two to three days where the patient did not receive antibiotics that would be considered for use as a part of the standard care for treating Staphylococcal infections. After several days a neurologist was consulted and they put epidural abscess on the differential diagnosis list and ordered an MRI that confirmed the diagnosis of an epidural abscess. The patient underwent the appropriate surgery, however, she suffered permanent neurological damage resulting in paralysis of the lower extremities.

In conclusion, diagnostic errors are preventable when evaluating a particular physicians decision making process but only when the hospital and physician are working to keep the best interest of the patient at the center of their efforts and attention. The outcome for the patients will be greatly enhanced when the physician both recognizes and corrects their thought pattern according to the state of the art in preventing diagnostic errors.

About the Author
Stephen Broomes, MD is a board-certified internal medicine physician with over 17 years of direct inpatient hospitalist experience. He is an experienced medical expert witness. Dr. Broomes can be reached at (678) 695-3765 or at

[1] Society to Improve Diagnosis in Medicine