13.1.6

13.1.6	Explain the difference between screening and diagnosis

As discussed previously “Screening” is the process of identifying seemingly healthy people, who may be at increased risk of a particular disease / condition. This will likely entail a test / series of tests which will yield either positive identification of risk or NOT a positive identification of risk (this is similar to a negative result but since the purpose of screening is to identify those at risk rather than those NOT at risk of a given condition / disease).

If / when the screening test(s) yield a positive result that an individual is at increased risk then they referred onwards for to a health care practitioner to offered advise / counselling required in order to offer a diagnostic test, in order to better determine if said individual has the condition / disease. Such a refinement process (or screening pathway) is preferred as it due to the logistical costing (financially / emotionally / physical well being / etc) of applying diagnostic testing to everybody.

One such example would be the use of colonoscopy for routine screening of colon cancer. Whilst this is effective testing technique there is a risk of colon perforation by the endoscope head of around 1 in 1400 people, in which emergency surgery would be required to repair the damage. Couple this, with potential post-surgical recovery period of up to 3 months, the cost of care in such events oft outweigh the potential savings of early diagnosis.

https://www.gov.uk/guidance/nhs-population-screening-explained
http://www.nhs.uk/Livewell/Screening/Pages/screening.aspx
https://www.verywellhealth.com/whats-a-bowel-perforation-797590