False Positive
- A test indicates presence of a condition or attribute that is actually absent.
- Occurs across domains such as medical testing, security screening, and quality control.
- Can cause unnecessary follow-up, stress, delays, or disruptions and usually requires confirmation procedures.
Definition
Section titled “Definition”A false positive is a type of error that occurs when a test or evaluation incorrectly indicates that a certain condition or attribute is present, when in reality it is not.
Explanation
Section titled “Explanation”False positives can arise in many contexts, including medical testing, security screenings, and quality control checks. They occur when an initial test result signals the presence of a disease, prohibited item, or defect that does not actually exist. Consequences range from personal stress and unnecessary medical follow-up to delays, disruptions, and unnecessary searches. Reducing false positives relies on accurate and reliable tests and appropriate follow-up procedures, such as additional confirmation testing or verification by trained personnel.
Examples
Section titled “Examples”Medical testing (HIV example)
Section titled “Medical testing (HIV example)”A person may undergo a blood test for HIV, and the test may come back positive, indicating that the person has the virus. However, further testing may reveal that the person is actually HIV-negative, and the initial positive result was a false positive.
Security screening (scanner/weapon example)
Section titled “Security screening (scanner/weapon example)”A security scanner may indicate that a person has a weapon on their person, causing the person to be detained and searched. Further investigation may reveal that the person was carrying a harmless object that the scanner mistook for a weapon, resulting in a false positive.
Use cases
Section titled “Use cases”- Medical testing
- Security screenings
- Quality control checks
Notes or pitfalls
Section titled “Notes or pitfalls”- False positives can produce significant consequences, including unnecessary stress, further testing or treatment, delays, and disruptions.
- Prevention and mitigation require accurate, reliable tests and established follow-up procedures such as confirmation testing or verification by trained personnel.