Preventative care

• Primary prevention is prevention before onset of disease
• Secondary prevention is the detection of asymptomatic disease
• Tertiary prevention is the prevention of the complications of symptomatic disease

These distinctions are useful in concept but blurred in practice. For example, treating hypertension is secondary prevention if considering the condition in its own right but primary prevention if considering stroke, left ventricular failure or renal failure. Stopping smoking is primary prevention of lung cancer but tertiary prevention of existing chronic obstructive pulmonary disease.

ref: Principles of Ambulatory Med 4e L Randol Barker et al