The aim is to find the one condition that is not covered by an organised national screening effort. Screening is justified when a disease is frequent, detectable in an early silent phase, testable by an acceptable method and treatable to better effect when caught early. Diabetes fits and is screened within the national non-communicable disease initiative. Refractive errors are actively looked for during school eye examinations and vision screening drives, qualifying them as a screened condition. Cervical cancer is one of the three cancers (with breast and oral) included in population based screening under the NCD programme. Dental caries, although extremely common, is tackled through oral hygiene promotion, fluoride use and treatment of detected cases rather than through a dedicated mass screening programme. Working through the choices, the outlier without a national screening programme is dental caries. \[\boxed{\text{Dental caries}}\]