Which level of prevention involves screening to detect disease early, often before symptoms appear?

• A. Primary
• B. Secondary
• C. Tertiary
• D. Quaternary

Answer: (B)

Screening to detect disease early, before symptoms arise, is a hallmark of secondary prevention. The goal at this level is to find illness at an asymptomatic stage so timely treatment can prevent progression, reduce complications, and improve outcomes. By contrast, primary prevention aims to stop the disease from developing in the first place through measures like vaccines and risk factor modification. Tertiary prevention focuses on reducing disability and complications once a disease is established, through rehab and ongoing management. Quaternary prevention centers on avoiding overmedicalization and unnecessary interventions. Examples of secondary prevention include mammography, colonoscopy, and routine screening tests that catch conditions early.