Screening tools / test
SAQ. Shortly discuss screening tools with its advantages & disadvantages.
Answer:
- Screening is the application of a screening test to a large number of asymptomatic people with the aim of reducing morbidity or mortality from a disease.
Wilson and Junger’s criteria (WHO recommended)
- Is the disease an important public health problem?
- Is there a suitable screening test available?
- Is there a recognisable latent or early stage?
- Is there effective treatment for the disease at this stage which improves prognosis?
Pre-requisites of screening tests
- Cheap
- Acceptable
- Easy to perform
- Safe and gives a valid result in terms of sensitivity and specificity
Examples of large-scale screening programs
- Cancer screening for Breast, Colorectal, Cervical
- Diabetic eye screening program
- Fetal anomaly screening program
- Infectious diseases in pregnancy screening program
- Newborn and infant physical examination screening program
- Newborn blood spot screening program
- Newborn hearing screening program
- Sickle-cell anemia and thalassemia screening program
Problems with screening include
- Over-diagnosis (of a disease that would not have come to clinical attention on its own or would not have led to death)
- False reassurance
- Diversion of resources from investments that could control the disease more cost-effectively