Biostats

Question 1

Sensitivity

Answer 1

TP/TP+FN

Question 2

Specificity

Answer 2

TN/TN+FP

Question 3

PPV

Answer 3

TP/TP+FP

Question 4

NPV

Answer 4

TN/TN+FN

Question 5

Odds Ratio

Answer 5

AD/BC

Question 6

Relative risk

Answer 6

(A/A+B) / (C/C+D)

Question 7

Attributable risk

Answer 7

(A/A+B) - (C/C+D)

Question 8

Relative risk reduction

Answer 8

1 - AD/BC

Question 9

Absolute risk reduction

Answer 9

(C/C+D) - (A/A+B)

Question 10

NNT

Answer 10

1/ARR

Question 11

NNH

Answer 11

1/AR

Question 12

Vd

Answer 12

Amt in body / Plasma concentration

Question 13

Half life

Answer 13

0.7 x Vd / Cl

Question 14

Clearance

Given an elimination constant?

Answer 14

U x V / P

Vd x Ke

Question 15

Loading dose

Answer 15

Cp x Vd / F

Question 16

Maintenance dose

Answer 16

Cp x Cl x tau / F

Question 17

Cardiac output (w/ oxygen values)

Answer 17

Rate of consumption / (Arterial - Venous)

Question 18

MAP (given systolic and diastolic)

Answer 18

2/3 diastolic + 1/3 systolic

Question 19

RBF (given RPF and Hct)

Answer 19

RBF = RPF / (1-Hct)

Question 20

Filtration fraction

Answer 20

GFR/RPF

Question 21

pH (given ABG)

Answer 21

6.1 + log (HCO3/(.03*PCO2))

Question 22

PCO2 (given HCO3)

Answer 22

1.5(HCO3) + 8 +/- 2

Question 23

Physiologic dead space

Answer 23

Vt x ((PaCO2 - PeCO2)/PaCO2)

Question 24

PVR (given pressures and output)

Answer 24

(P pulm artery - P L atrium) / C.O.

Question 25

Alveolar gas equation

Answer 25

PAO2 = PIO2 - (PaCO2/R)