Equation Review Flashcards
1
Q
Sensitivity
A
TP/(TP+FN)
2
Q
Specificity
A
TN/(TN+FP)
3
Q
Positive predictive value
A
TP/(TP+FP)
4
Q
Negative predictive value
A
TN/(FN+TN)
5
Q
Odds ratio (for case control studies - retrospective)
A
OR = (a/c) / (b/d) = ad/bc
6
Q
Relative risk (often cohort - prospective)
A
RR = a/(a+b) / c/(c+d)
7
Q
Attributable risk
A
AR = a/(a+b) - c/(c+d)
8
Q
Relative Risk Reduction
A
RRR = 1 - RR
9
Q
Absolute Risk Reduction
A
ARR = c/(c+d) - a/(a+b)
10
Q
Number needed to treat
A
NNT = 1/ARR (inverse of ARR)
11
Q
Number needed to harm
A
NNH = 1/AR (inverse of AR)
12
Q
Hardy-Weinberg Equilibrium
A
p^2 + 2pq + q^2 = 1
p + q = 1
13
Q
Volume of distribution
A
Vd = amount of drug in body / plasma drug concentration
14
Q
Half-life
A
t1/2 = 0.693 * Vd / CL
15
Q
Drug clearance
A
CL = rate of elimination of drug / plasma drug concentration = Vd * Ke (elimination constant)
