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Diagnostic Overshadowing Worsens Health Disparities


A man with grey hair is watching the laptop screen.

By Rick Rader, MD, FAAIDD, FAADM, DHL (hon), Director, Habilitation Center, Orange Grove Center and Patricia McGaffigan, Vice President, Institute for Healthcare Improvement (IHI)

Diagnostic overshadowing—defined as the attribution of symptoms to an existing diagnosis rather than a potential co-morbid condition—has been a problem for decades and is only recently getting the attention it deserves.

This was first described in 1982 as related to diagnostic misattribution in patients with mental health disorders. Medical literature includes extensive evidence that diagnostic overshadowing exists within the interactions of clinicians with patients of all ages who have physical disabilities or previous diagnoses or conditions such as, but not limited to:

  • autism
  • mobility disabilities
  • neurological deficits
  • LGBTQ+ identifications
  • history of substance abuse
  • low health literacy 
  • obesity 
  • psychiatric/mental health disorders

Widespread Nature of Diagnostic Overshadowing
Diagnostic overshadowing is more than an inconvenience. It is a form of diagnostic error that can cause harm to any patient on the care continuum, regardless of age. It also can occur to virtually any patient with a pre-existing diagnosis or condition, as well as the more than 1 billion people who are estimated to experience a disability – corresponding to about 15% of the world's population. Additionally, up to 190 million people (3.8%) 15 years and older have significant difficulties in functioning, often requiring healthcare services. The number of people experiencing disability is increasing due to a rise in chronic health conditions and population aging.

Lack of Accessible Data
In many clinical scenarios, providers do not have access to aggregated data that would identify a particular patient as someone who is at greater risk for diagnostic overshadowing. These data can help a clinician identify an individual who is more likely to experience health disparities not only due to their pre-existing conditions or disabilities, but also due to:

  • race
  • ethnicity
  • language
  • sexual orientation/gender identity
  • geography
  • health insurance coverage
  • access to providers and pharmacies
  • other social determinants of health

Clinicians need to take into consideration how a patient's race, social class and gender identification, along with disabilities and previous diagnoses, may affect their evaluation. Clinicians can use an “intersectional approach” to care, acknowledging systemic discrimination due the aforementioned factors. In healthcare, an intersectional approach emphasizes patients’ attitudes towards their providers and the efficacy of their treatment plans.

If we do not accurately and comprehensively assess and understand patients during their encounters with the healthcare system to begin with, the risk of diagnostic overshadowing is further exacerbated. 

Impact of Clinician Training and Time 
Diagnostic overshadowing stems from cognitive bias. Once an initial diagnosis has been made, momentum sometimes takes hold and reduces a clinician's ability to consider other alternatives. This bias can affect future patient workups and how handoffs to other providers are framed.

Additionally, time pressures faced by clinicians can cause them to hurry or to be impatient. A 2019 article in the Journal of General Internal Medicine found that, after prompting a conversation with a patient about their concerns, clinicians interrupted patients after a median of only 11 seconds and came away with an understanding of the patient's concerns in only 36% of the encounters. As a result of time pressures and other factors, patients are often unable to present a complete or accurate narrative of their symptoms, medical histories and current medications.

Then, there’s the issue of training. Most clinicians do not have training, experience and skills grounded in treating individuals with disabilities – again putting these individuals at increased risk for diagnostic overshadowing. Virtually every major report addressing the poor health of persons with disabilities has called for improvements in the training of healthcare. What’s needed is a “re-training” of clinicians’ brains to learn how to avoid “lapsing” into cognitive bias. 

One-third of U.S. physicians do not know their legal requirements under the Americans with Disabilities Act (ADA). Some U.S. medical schools provide disability competency training to be incorporated into all medical, nursing, healthcare professional and allied health professional schools, as well as postgraduate residency, fellowship and continuing medical education programs.

Suggested Actions
The Joint Commission recommends the following suggested actions to help recognize and address diagnostic overshadowing among groups experiencing health disparities.

  1. Create an awareness of diagnostic overshadowing during clinical peer and quality assurance reviews and address it in training and education programs. This should encompass curricula focused on the care of individuals with disabilities and within other populations experiencing health disparities in residency, fellowship and continued medical education programs for physicians, physician assistants and nurse practitioners  . 
  2. Remember, the audience that is capable of helping us prevent and detect diagnostic overshadowing is broader than those who have diagnostic privileges. Many members of the care team, including nurses, patients and their family members are critical to identifying diagnostic errors and advancing improvement. This can also be integrated into the diagnostic excellence priorities and work of quality and safety leaders.
  3. Use listening and interviewing techniques designed to gain better patient engagement and shared decision making.
  4. Collect and aggregate data about pre-existing conditions and disabilities and create EHR prompts for clinicians.
  5. Use an intersectional framework when assessing patients in groups prone to diagnostic overshadowing to overcome cognitive biases and look beyond previous diagnoses.
  6. Review your organization’s ADA compliance using the added perspective of diagnostic overshadowing to ensure that it meets the needs of patients with physical disabilities.  It’s important to use facilities required by ADA law, including testing laboratories, exam tables, imaging machines and scales.

The silver lining is that many organizations are well on their way and winning practices are already popping up in the literature. Awareness is often half the battle and this really is the best time in modern medicine to make sure that NO patients’ concerns are overshadowed by existing diagnoses.

Dr. Rick Rader is the physician director of the Habilitation Center at the Orange Grove Center in Chattanooga, TN, where he is responsible for the identification and initiation of innovative healthcare programs for people with intellectual and developmental disabilities across the life span. He serves as the President of the American Association on Health and Disability, He is a co-founder of the American Academy of Developmental Medicine and Dentistry and served on the Presidents Committee for People with Intellectual Disabilities. He currently serves as a Presidential appointee to the National Council on Disability.

Patricia McGaffigan, MS, RN, CPPS, is President, Certification Board for Professionals in Patient Safety, and Vice President at the Institute for Healthcare Improvement where she is IHI’s senior sponsor for the National Steering Committee for Patient Safety. She is the former Chief Operating Officer and Senior Vice President of Safety Programs at the National Patient Safety Foundation. Patricia is a Certified Professional in Patient Safety (CPPS), a graduate of the AHA-NPSF Patient Safety Leadership Fellowship Program and member of the Joint Commission National Patient Safety Committee, the Joint Commission Journal on Quality and Patient Safety Editorial Advisory Board, and the Advisory Committee of the Coalition to Improve Diagnosis. Patricia serves as a Board Member of the Massachusetts Coalition for the Prevention of Medical Errors and on Planetree’s Person-Centered Certification Committee.