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Flashcards in Basics Deck (14)
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1

Define sensitivity

The ability to identify positive results
The ability to detect small amounts of analyte
Proportion of people that have the disease that will test positive

2

Calculate sensitivity

Sensitivity = (TP/TP + FN) X 100

3

Define specificity

The ability to identify negative results
The selectivity of an assay reaction
Proportion of people known not to have a dz that will test negative for it

4

Calculate specificity

Specificity = (TN/TN + FP) X 100

5

Define Type I error (α)

false positive rate

6

Calculate Type I error (α)

1 – specificity

7

Define Type II error (β)

false negative rate

8

Calculate Type II error (β)

1- sensitivity

9

Define PPV

Proportion of positive test results that are true positives (correct diagnoses)

10

Calculate PPV

Positive Predictive Value (Precision Rate) = TP/TP + FP (total positive calls)

11

Define NPV

Proportion of negative test results that are true negatives (correct diagnoses)

12

Calculate NPV

Negative Predictive Value = TN/TN + FN (total negative calls)

13

As the prevalence of a condition increases, does the sample size required to detect the condition increase or decrease?

Decrease

14

Does the number of animals that must be sample in order to achieve a certain level of confidence increase or decrease as the colony size decreases?

Increase (BB pg 383)