Screening is the process of determining whether or not a person has a medical issue. People who do not show any signs of the disease or ailment are frequently given a screening test. A person who has risk factors for an illness or disorder may be examined more frequently. Confirmatory testing may be used to assess whether a person is at risk for a disease or disorder after they have been recognised as being at risk. Other procedures that are more invasive or expensive than screening tests, or that pose larger health risks, are routinely used to confirm a medical diagnosis. To save money and prevent exposure to radiation or other potential risks, screening and confirmatory procedures are frequently combined. In some cases, a confirmatory test may be performed beforehand to ensure that the screening test is the next logical step.Screening tests are usually painless and include exposing test subjects to the least amount of danger or injury possible, often without the use of invasive procedures or technologies.