EXAM3_WS4_Medical_Decision_Making

Question 1

PREVALENCE

Answer 1

The % of a population that is diseased

Prevalence%=( # Diseased/Total Population) X 100

Question 2

Sensitivity

Answer 2

The percentage of True Positives within a diseased population

SN= TP/diseased or

SN= TP/(TP +FN)

diseased population = TP + FN

Question 3

Specificity

Answer 3

The percentage of True Negatives within a non-diseased population

SP= TN/(TN + FP)

Non-diseased Population= TN + FP

Question 4

Sensitivity vs Specificity

Answer 4

SPin rules the disease IN (if test positive)

SNout rules the disease OUT (if test negative)

Question 5

What type of diseases do you need your test to be 100% Specificity?

Answer 5

Serious UNTREATABLE DISEASES
(you have to be sure- before you tell someone or they might kill themselves)

IE: Huntingtons disease

Question 6

What type of diseases do you need your test to be 100% Sensitivity?

Answer 6

Serious diseases where TREATMENT IS CRITICAL

ie: PKU

Question 7

PPV

Answer 7

Positive Predictive Value
Likelihood a positive test is TRULY POSITIVE

PPV% = TP/total positives x 100
(total positives= TP + FP)

Question 8

NPV

Answer 8

Negative Predictive Value

NPV%= TN/(TN+FN) X 100

Likelihood a negative test is truly negative