Demographic information about a specific subset of patients can help physicians recognize conditions they do not expect to find in the larger population.
The WHO Clinical Staging System for HIV/AIDS allows physicians in resource-limited settings to make clinical decisions based on patient clinical features instead of laboratory tests.
Those who survived Hurricanes Katrina and Rita faced homelessness and physical and mental health problems that created ethical dilemmas for physicians.
Clinical decision making calls for use of both explicit and tacit knowledge despite evidence-based medicine's assumption that explicit information is sufficient.