underdiagnosis

Underdiagnosis refers to a situation in which a person has a health condition or disease but the condition has not been diagnosed by a health professional. It contrasts with misdiagnosis, where a diagnosis is incorrect, and with overdiagnosis, where a condition is diagnosed but would not cause harm if left untreated. Underdiagnosis can occur for various reasons and affects individuals and populations, leading to delayed or absent treatment and a distorted view of disease burden.

Common drivers include limited access to healthcare, socioeconomic barriers, and shortages of trained clinicians; non-specific or mild symptoms; atypical disease presentations; lack of routine screening in certain populations; cultural, linguistic, or stigma-related barriers; and biases in clinical assessment or guideline-based care. Data limitations and under-reporting in surveillance systems can also mask true prevalence.

Consequences include progression of disease before treatment, worse outcomes, higher mortality, reduced quality of life, and greater long-term healthcare costs. On a population level, underdiagnosis can hinder public health planning and resource allocation, and studies of disease burden may underestimate prevalence.

Examples are common in mental health, where conditions like depression or anxiety may go undetected, in autoimmune diseases with nonspecific symptoms, and among underserved groups such as older adults or people in low-resource settings. The issue also affects chronic conditions identified through screening, where access or adherence to screening tests is uneven.

Efforts to reduce underdiagnosis include expanding access to primary care and specialty services, implementing routine and targeted screening, using validated assessment tools, training clinicians in culturally competent care, and improving health information systems to better capture diagnosed and undiagnosed cases. Community engagement and patient education can also promote timely evaluation of symptoms.