Screening

What is screening?

Essentially, screening is a tool in the primary prevention of disease. It is designed to find disease at a treatable, asymptomatic stage and prevent it from becoming untreatable. This is because it is often cheaper and more efficacious to put the effort into finding the disease than it is to treat it once it becomes clinically apparent.

Criteria

Some clever dudes called Wilson and Junger came of a bunch of criteria in 1968. Amazingly, they manage to create a PDF of their findings; pretty impressive given the technology at the time.

The condition shoud be:

• important
• prevalent
• has an early, detectable stage

The diagnostic test/examination should be

• acceptable to patients (i.e. not involve being molested by a parrot)
• cheap
• easy to do/access
• highly sensitive (few false negatives)
• highly specific (few false positives)
• available (make sure a test actually exists)

The treatment should be:

• effective (there's no point in detecting a condition that is terminal)
• cost-effective
• available (make sure a treatment actually exists)

Screening examples

• Cervical screening
• Breast screening
• Blood pressure
• Diabetes
• Depression