Diagnostic overshadowing occurs when healthcare providers mistakenly attribute new physical symptoms to a patient’s existing health condition, particularly a mental health condition or a disability. This can lead to delays in diagnosis or a complete failure to identify the true underlying medical problem, posing a significant challenge within healthcare.
What is Diagnostic Overshadowing?
Diagnostic overshadowing occurs when a healthcare professional focuses too heavily on a patient’s known diagnosis, causing them to overlook or misinterpret new symptoms. The National Institute of Clinical Excellence (NICE) defines this as the tendency to attribute all behavioral, emotional, physical, and social issues to a person’s pre-existing condition, disregarding other potential causes.
For instance, a person with depression reporting persistent fatigue might have symptoms dismissed as “just their depression,” while a treatable condition like anemia goes undiagnosed. Similarly, an individual with an intellectual disability experiencing abdominal pain might have discomfort attributed to “challenging behavior” rather than a physical issue like appendicitis. The core mechanism involves an existing condition “overshadowing” the clinician’s perception, preventing a thorough assessment of new symptoms.
Why Diagnostic Overshadowing Occurs
Several factors contribute to diagnostic overshadowing, including cognitive biases and systemic issues within healthcare. Clinicians are susceptible to biases that influence their diagnostic reasoning. Anchoring bias, for example, causes a healthcare provider to rely too heavily on an initial piece of information, such as a patient’s existing diagnosis.
Confirmation bias also plays a role, where providers may selectively interpret evidence to confirm initial assumptions about symptoms relating to a pre-existing condition. Premature closure, a tendency to stop gathering information once an initial diagnosis seems plausible, can prevent thorough exploration. Time constraints and fragmented care systems can exacerbate these biases, limiting comprehensive assessments. A lack of specific training among healthcare professionals regarding co-occurring conditions, especially in populations with intellectual disabilities or severe mental illnesses, also contributes.
How Diagnostic Overshadowing Affects Patients
Diagnostic overshadowing has serious consequences for patient health, often leading to delayed or missed diagnoses for treatable conditions. When new symptoms are misattributed, underlying physical health problems can worsen due to a lack of timely intervention. This can result in increased suffering, prolonged illness, and a reduced overall quality of life for affected individuals. Patients may also lose trust in healthcare providers, potentially leading to avoidance of future care.
Certain populations are disproportionately affected. Individuals with severe mental illnesses, intellectual disabilities, and autism spectrum disorder are particularly vulnerable, as their behaviors or communication styles may be misunderstood or attributed solely to their existing diagnoses. For example, people with intellectual disabilities on average die 16 years earlier than their peers without intellectual disabilities, partly due to diagnostic overshadowing contributing to inadequate treatment for conditions like diabetes, hypertension, and obesity. Other groups at increased risk include those with:
- Physical and cognitive disabilities
- Neurodevelopmental disorders
- Obesity
- Low health literacy
- Substance use disorders
Steps Toward Better Diagnosis
Addressing diagnostic overshadowing requires a multi-faceted approach involving both patients and healthcare providers.
For Patients and Caregivers:
- Clearly communicate all symptoms, even those seemingly unrelated to an existing condition.
- Advocate for thorough investigations.
- Bring a trusted family member or advocate to appointments to ensure all concerns are voiced and understood.
- Seek second opinions if symptoms persist or a diagnosis feels incomplete.
For Healthcare Providers:
For healthcare providers, ongoing education and awareness about diagnostic overshadowing are important to mitigate its effects. This includes training on cognitive biases and developing strategies to challenge assumptions during assessments. Comprehensive evaluations, active listening to patient concerns, and considering a broad range of differential diagnoses are also valuable practices. Interdisciplinary collaboration among different healthcare specialties can provide a more holistic view of a patient’s health, helping to prevent isolated interpretations of symptoms.