Wilson and Jungner criteria (WHO, 1968) for a valid screening programme include that the natural history of the condition should be 'adequately understood.' A disease fails this criterion most critically when:

• A There is no available treatment for the disease
• B The latent period cannot be distinguished from the symptomatic phase ✓
• C The preclinical detectable phase (PCDP) is very long
• D The disease primarily affects elderly populations

Explanation

Wilson-Jungner criteria require that the natural history of the disease — from latent phase through preclinical phase to symptomatic phase — is adequately understood to ensure that screening during the preclinical detectable phase (PCDP) leads to improved outcomes. If the latent period cannot be distinguished from the symptomatic phase (i.e., the disease goes directly from latent to clinical without a measurable preclinical phase), screening has no window in which to intervene. A long PCDP is actually favorable for screening. Lack of treatment is a separate criterion (acceptable treatment must exist). Age distribution does not affect this criterion.

Reference: Park's Textbook of Preventive and Social Medicine, 27th ed.

High-yield for: NEET PGINI-CETNExTFMGEUSMLEPLABMRCP

Written and medically reviewed by the StethoPrep medical team.