Missed Diagnosis and Patient Safety

Introduction

A physician makes many decisions every day while carrying out their professional responsibility. When patients come into the office or hospital setting, they expect that physicians will articulate their concerns, use their professional skills to arrive at a diagnosis and solve the problems. Physicians are well-trained to make reasonable sense of what brings patients to their attention. Training through medical school, continuous professional development, and experience provides most physicians with the skills to make a correct and timely diagnosis and resolve patient concerns. Our healthcare systems are also equipped with powerful diagnostic resources with proven high accuracy to reduce the incidence of missed diagnoses.

Despite all these factors, physicians do occasionally miss diagnoses with a negative implication for quality care and patient safety.

Missed diagnosis is defined as the incorrect diagnosis of a morbid condition.^[1]

The National Academies of Sciences, Engineering, and Medicine defined diagnostic error as the failure to (a) establish an accurate and timely explanation of the patient’s health problem(s) or (b) communicate that explanation to the patient. Simply put, these are diagnoses that are delayed, wrong, or missed altogether.

These categories overlap, but examples help illustrate some differences:

• A delayed diagnosis is a case where the diagnosis should have been made earlier. Delayed diagnosis of cancer is by far the leading entity in this category. A significant problem in this regard is that there are very few good guidelines for making a timely diagnosis, and many illnesses aren’t suspected until symptoms persist or worsen.

• A wrong diagnosis occurs, for example, if a patient truly having a heart attack is told their pain is from acid indigestion. The original diagnosis is incorrect because the actual cause is discovered later.

• A missed diagnosis refers to a patient whose medical complaints are never explained. Many patients with chronic fatigue or chronic pain fall into this category, as well as patients with more specific complaints that are never accurately diagnosed.^[2]

 
Recent research suggests that family physicians and specialists are experiencing overwhelming circumstances in their practices. Many are stretched to the limit and experience a form of burnout. Many patients stayed home during the initial wave of the pandemic and are now more confident to visit their family physicians and specialists. As a result, clinics are experiencing a surge in patient visits, and specialists are dealing with backlogs in their waitlists. Surgeons have an impressive operative list that might take years to perform. In addition, a few physicians and health care professionals are leaving for other provinces or choosing to leave practice entirely. To add to the stress of the situation, supportive healthcare professionals such as nurses, licensed practical nurses and medical office assistants are also experiencing shortages in the workforce, creating a gap. Our emergency rooms are overwhelmed. Seeing that wait times in our urban emergency rooms are skyrocketing is disheartening.  Under these very pressing and demanding situations, the risk of misdiagnosis, missed diagnosis, delayed diagnosis, and medical errors is high.

According to the Patient Safety Institute, misdiagnoses, falls, infections and mistakes during treatment are the most common types of patient safety incidents. Those who have experienced a patient safety incident commonly cite distracted or overlooked[CG1]  health care practitioners (HCPs) as the most significant contributing factors that led to the incident.^[3]

While we may not know the exact data, some surveys estimate that about 7.5 percent of Canadian patients experience missed diagnoses in their lifetime. ^[4]

In a study of Interval cancers after colonoscopy: the importance of training, John Inadomi discovered the rate of 7.9% of missed diagnosis of colorectal cancers after colonoscopy. Evidence in the study supported missed diagnoses from colonoscopy quality rather than tumour biology.^[5]

Another study by Harminder Singh, Zoann Nugent, Alain A Demers, Charles N Bernstein, Rate and predictors of early/missed colorectal cancers after colonoscopy in Manitoba: a population-based study presents a 3-year analysis of missed cancer after colonoscopy, where 1 in 13 colorectal cancers are missed diagnoses. Factors responsible are either tumour biology, bowel preparation or procedural difficulty. ^[6]

In a study of Determinants of appendicitis outcomes in Canadian children by Li Hsia Alicia Cheong and Sherif Emil , a higher rate of misdiagnosis was associated with lower age, female gender, non-children's hospitals, and western Canada. ^[7]

A review of interval breast cancers diagnosed among participants of the Nova Scotia Breast Screening Program discovered that the rate of missed cancers per 1000 women screened was one-half of the true interval rate among women screened annually (for ages 40-49 years, 0.45 vs 0.93; for ages 50-69 years, 1.08 vs 2.22)^[8]

Missed diagnosis occurs in the clinical and hospital setting in Canada and is a significant cause of patient safety incidents. Various factors are responsible for the prevalence of missed diagnoses. In an overwhelming work environment, the risk of missed diagnosis or misdiagnosis is high. Physicians, health care providers and patients should work together to reduce its incidence to the minimum to prevent patient harm.

Poor handoffs, lack of feedback, limited support, and a complex diagnostic process contribute to the thousands of misdiagnosis-related hospital deaths yearly. ^[9]

Graber et al. divided diagnostic errors into three categories:

• No-fault errors, which result from factors outside the control of the physician or the healthcare system;
• System-related errors, which include technological or organisational barriers;
• Cognitive errors, which include inadequate knowledge, poor critical thinking skills, a lack of competency, problems in data gathering, and failure to synthesize information.^[10]

The Implication to Patient Safety

A 70-year-old male known hypertensive diabetic presented to the ER with spontaneous onset severe back pain of one-day duration. After history and focused physical examination, a tentative diagnosis of musculoskeletal pain was made. The patient was given Tylenol 3 for pain management and a muscle relaxant. He presented a day later to the ER with a ruptured aortic abdominal aneurysm.

A 65-year-old female known case of diabetes mellitus, rheumatoid arthritis wheelchair-bound called the family physician because of increased numbness at the extremities and inability to perform her usual activities of daily living. She requested an increased dose of muscle relaxant because of worsening extremity spasms. Family physicians approved an increased dose of muscle relaxant by telephone. They did not arrange any visit for a physical examination. Two days later, the patient presented to the ER with quadriparesis secondary to cervical spine erosive disease from rheumatoid arthritis.

A 60-year-old female presented to her family physician’s office for periodic medical evaluation. Her urinalysis revealed greater than 5 red blood cells. The family physician was late in reviewing her laboratory reports. After three months of assuming everything is normal, she called the family doctor, who then reviewed the labs with her. An urgent ultrasound confirmed the diagnosis of renal cell cancer with metastasis to the lungs.

A twenty-five-year-old First Nations female presented to her family physician in a solo, busy family practice clinic at around closing hours. She is known to the family medicine clinic to be a frequent clinic attendant with dysmenorrhea and STI concerns. After a short encounter, she was sent home with Naproxen for abdominal pain. She ended up in the ER two days later with ruptured ectopic pregnancy.

A 56-year-old First Nations male presents with chest discomfort, diaphoresis and anxiety. He is known in the local ER as an individual with a history of substance use disorder. The attending physician assumed he was experiencing typical panic attacks and drug withdrawal symptoms. He sent him home without any investigation with a week’s course of diazepam and advised him to follow up with his family doctor. Two days later, he was transferred to a tertiary center for acute ST-elevation myocardial infarction.

While these case scenarios are not actual cases, they are very similar to patient situations that can result in diagnostic errors and the severe consequences that could result from such errors. We cannot over-emphasize the safety implication of diagnostic errors; physician leaders, administrators, educators and physicians must shine their eyes to prevent this situation. This is even more important in our present circumstance, where resources are stretched, and healthcare providers are overwhelmed.

According to the Society to Improve Diagnosis in Medicine, diagnostic error is one of the most important safety problems in health care today and inflicts the most harm. Significant diagnostic errors are found as the cause of death in 10% to 20% of autopsies, suggesting that 40,000 to 80,000 patients die annually in the U.S. from diagnostic errors. Patient surveys confirm that at least one person in three has firsthand experience with a diagnostic error, and researchers have found that diagnostic errors—not surgical mistakes or medication overdoses—account for the most considerable fraction of malpractice claims, the most severe patient harm, and the highest total of damages/settlement payouts. It is likely that most of us will experience at least one diagnostic error in our lifetimes, sometimes with devastating consequences.^[11]

COVID has taken its toll on the health of our communities; allowing diagnostic error to inflict its negative consequences upon our patients' safety is truly adding insult upon injury.  I call on my physician colleagues, physician leaders, health care administrators, and allied health care providers to pay attention to patient care and the health care delivery system and actively implement strategies to avoid diagnostic errors to prevent further patient harm.