Overview
Screening Is a Probability Decision
Screening is offered to people who do not have symptoms, with the aim of finding disease or a precursor before it becomes clinically apparent.
Screening is offered to people who do not have symptoms, with the aim of finding disease or a precursor before it becomes clinically apparent. A screening result changes the probability that disease is present; it does not establish a diagnosis. A positive result therefore requires an appropriate diagnostic pathway, while a negative result lowers—but does not eliminate—risk. The value of a screening programme depends on more than the test itself. The disease must be sufficiently important, earlier detection must offer a meaningful benefit, and the harms of false-positive results, additional procedures, anxiety, and overdiagnosis must be acceptable. This is why a test that seems helpful for one age group or risk category may not be recommended for another. Health promotion is broader than screening. It includes reducing modifiable risk, supporting protective behaviours, and helping people make informed choices that fit their goals and circumstances. The nurse’s first task is not to list every available test. It is to identify which preventive decision is relevant to this person now.
