In the natural history of a chronic disease, there exists a point beyond which treatment produces progressively less benefit than if the disease had been detected and treated earlier. A screening programme is worthwhile partly because it detects cases before crossing this point. This point is called the:

• A Latent period
• B Critical point ✓
• C Incubation period
• D Detectable preclinical phase

Explanation

The critical point in natural history is the juncture before which therapy is more effective than after it; effective screening must catch disease in the preclinical detectable phase that lies before this point. The latent or incubation period denotes time between exposure and detectability, and the detectable preclinical phase is the window during which screening can find disease, not the therapeutic turning point itself.

Reference: Park's Textbook of Preventive and Social Medicine, 26th ed.

High-yield for: NEET PGINI-CETNExTFMGEUSMLEPLABMRCP

Written and medically reviewed by the StethoPrep medical team.