LEC 2 Immunology Assays and Techniques Flashcards
Dr. Jeanette Ramos, MD Memorize formulas for sensitivity, specificity, positive predictive value, and negative predictive value and be able to apply the formulas to question scenarios Understand the function of different methodologies Use the knowledge of methodology types to select the appropriate test for clinical use
What is sensitivity?
Ability of a test to identify those that have the disease
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What is the formula for sensitivity?
TP/(TP+FN)
TP = True Positive; FN = False Negative
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What is specificity?
Ability of a test to identify those without a disease
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What is the formula for specificity?
TN/(TN+FP)
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What is a positive predictive value?
Probability that a person who has a positive test has the disease
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What is the formula for positive predictive value?
TP/(TP+FP)
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What is a negative predictive value?
Probability that the person with a negative test does NOT have the disease
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What is the formula for negative predictive value?
TN/(TN+FN)
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What is ELISA and what is its function?
Enzyme-linked immunosorbent assay
Used to detect the presence of either a specific antigen or a specific antibody in a patient’s blood sam
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What is the difference b/w Direct and Indirect ELISA?
- Direct: uses a singular antibody/antigen that is directly coupled to a color-generating enzyme to detect the antigen in the pt’s blood
- Indirect: uses 2 antibodies/antigens. The second one is coupled to a color-generating enzyme that detects the antigen-antibody complex
Slide 3 Harley
