Skip to Main Content


The typical natural history of many diseases and conditions suggests that at some point in the life course their biological onset occurs, during or after conception, and progresses at varying rates until it become clinically evident. This interval may be short, such as for neonatal hearing loss, or long-term, as in Alzheimer’s disease. Some diseases may never become clinically manifest and thus afford little clinical harm. This may occur for various reasons including biological variation, often not well understood, or the occurrence of competing clinical events, or possibly natural or clinically mediated environmental modification (called “primary prevention”). Important to the discussion here, the harms of nascent diseases and conditions also may be mitigated, deferred or eliminated by the early and asymptomatic detection of disease; that is, disease screening (also called “secondary prevention”). However, even when an overt clinical illness is already present, “tertiary prevention” can offer rehabilitative and other clinical interventions that may deter disease progression and help return the patient to a healthier state.

Disease screening activities usually take two general forms: (a) screening for biological disease antecedents that are part of known biobehavioral pathogenetic pathways to overt disease, such as abnormal blood cholesterol or blood pressure levels; or (b) screening directly for metabolic, physiological, behavioral, or anatomic markers of the disease itself, such as serological levels of a biomarker secreted by a tumor or a series of clinical symptom reports indicative of an emerging mental illness. In addition, preliminary screening might be conducted for factors that indicate increased risk of disease occurrence, irrespective of whether they are part of the pathogenetic mechanism. This highlights the fact that screening may be done in stages, for instance by screening first for general disease susceptibility and/or risk, such as for certain demographic, anatomic or behavioral characteristics. After the disease is detected, this would in turn be followed by provision of clinically appropriate treatment(s) to cure or to prevent the progression of pathophysiological processes that would otherwise cause overt clinical manifestations and individual harm. Thus, some screening tests may also be diagnostic tests, although staged screening is becoming more common to narrow the indications for the use of diagnostic procedures. This may be seen as greater adherence to the trend in “precision medicine,” although this concept can be somewhat controversial.1 Disease screening may be applied to community (e.g., mass screening), as well as clinical populations, depending on the effectiveness and emergent nature of the situation, but there is little point in screening if follow-up resources to address findings are not available.

The term “disease screening” should be used with clarity, as it may be part of a larger, comprehensive health maintenance or health surveillance program, and so the general definition of disease screening may not fit all situations. In addition, since many generally healthy individuals will have some at least temporary symptoms and feelings of ill-health at various times, the criterion that screened patients ...

Pop-up div Successfully Displayed

This div only appears when the trigger link is hovered over. Otherwise it is hidden from view.