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False Negative

  • A testing error where a result indicates a person does not have a condition even though they do.
  • Can delay diagnosis and treatment in medical contexts, and allow threats to go undetected in other domains.
  • Occurs across settings such as medical testing, criminal justice, and security screening.

A false negative is an error that occurs when a test result indicates that a person does not have a particular condition, disease, or characteristic, when in fact they do. It is the opposite of a false positive.

A false negative arises when a decision-making process or test fails to detect an existing condition. In medical testing, this means a test returns a negative result despite the presence of the condition being tested for. False negatives can lead to delays in diagnosis and treatment, potentially worsening health outcomes and increasing costs. Outside medicine, false negatives can allow dangerous individuals or objects to pass undetected.

A woman may take a home pregnancy test and receive a negative result, indicating she is not pregnant. If subsequent, more thorough testing by a doctor shows she is pregnant, the home test returned a false negative. This may cause delayed medical care or decisions based on incorrect information.

A person may be tested for HIV and receive a negative result indicating they are not infected. If later symptoms consistent with HIV lead to retesting and a positive result, the initial test produced a false negative. That initial result may have led the person to engage in risky behaviors or delay seeking care.

  • Medical testing (diagnosis and screening)
  • Criminal justice
  • Security screening
  • False negatives can cause delays in diagnosis and treatment, worsening outcomes and increasing costs.
  • In non-medical contexts, false negatives can permit dangerous individuals or objects to go undetected, potentially causing harm.
  • Reducing false negatives may involve using more accurate or more sensitive tests and considering the consequences of false negatives when making decisions based on test results.
  • False positive