TRUE POSITIVE TRUE NEGATIVE

• True Positive (TP) or Hit


  The test correctly identifies individuals who have the condition or the attribute is actually present in the individual being assessed
• True Positive


  • In a breast cancer screening, a mammogram correctly identifies a woman with breast cancer
  • A drug test accurately detects the presence of a banned substance in an athlete's urine sample
  • A psychological assessment correctly identifies a patient with depression based on their symptoms and responses
• True Negative (TN)


  The test correctly identifies individuals who do not have the condition being tested for. The test results are negative, and the individuals truly do not have the condition.
• True Negative


  • In a HIV screening, a blood test correctly identifies a person as HIV-negative when they do not have the virus
  • A COVID-19 test correctly identifies a person as negative for the virus when they are not infected
  • A plagiarism detection software correctly identifies an original piece of writing as not plagiarized
• False Positive (FP) or Type I Error


  The test incorrectly identifies individuals who do not have the condition as having it. The test results are positive, but the individuals do not actually have the condition.
• False Positive


  • In a drug screening at the workplace, a test mistakenly identifies an employee as using drugs when they are not
  • A security scanner at the airport alarms for explosives in a passenger's luggage, but upon inspection, it turns out to be a false alarm
  • A medical test for a rare disease incorrectly indicates that a person has the disease when they are healthy
• False Negative (FN) or Type II Error


  The test incorrectly identifies individuals who have the condition as not having it. The test results are negative, but the individuals actually have the condition.

  
• False Negative


  • A pregnancy test fails to detect the presence of pregnancy hormones in a woman who is actually pregnant
  • A cancer screening test fails to identify a tumor in a patient who later develops cancer symptoms
  • A cybersecurity system fails to detect a hacking attempt, allowing unauthorized access to sensitive data
• SEATWORK: CALCULATE THE TEST SENSITIVITY, SPECIFICITY, PPV AND NPV