# Lab Tests

The flashcards below were created by user julieaburch on FreezingBlue Flashcards.

1. Can calculate the revised probability (RP) from the initial probability (IP) of the diagnosis by knowing what 3 things? What is this called?
• The prior probability of the disease
• The probability of a positive test result with the disease
• The probability of a positive test result without the disease
• Called Bayes' Theorem
2. Good as screening test in disease with low prevalence; low false-negative (FN) rate; e.g. cancer screening tests, PSA, ELISA, HIV, etc.
High Sensitivity
3. A test with a low false-positive (FP) rate; good for confirming a positive obtained on a screening test; e.g. a positive ELISA HIV test must then be confirmed with a Western Blot assay
High Specificity
4. The percentage of patients with a "positive" result from a population with the disease (TPR)
Sensitivity of True Positive Rate (TPR)
5. The percentage of people with a "negative" test in a population without the disease (TNR)
Specificity of True Negative Rate (TNR)
6. False positive rate = ?
FPR = 1 - specificity
7. False negative rate = ?
FNR = 1 - sensitivity
8. SNOUT
• SeNsitivity "N" test rules out or Sn-N-Out disease:
• High sensitivity + Negative result --> Rules out diagnosis
9. SPIN
• SPecificity "P" rules IN or Sp-P-IN disease:
• High specificity + Positive result --> Rules in diagnosis
10. The ratio of the probability of finding a positive test in the presence of disease to the probability of a positive test in the absense of disease
Likelihood Ratio
 Author: julieaburch ID: 47797 Card Set: Lab Tests Updated: 2010-11-07 02:16:23 Tags: Lab Tests Folders: Description: Lab Tests Show Answers: