Equations

Question 1

Corrected serum calcium

Answer 1

corrected serum calcium= ((4-albumin) X 0.8) + measured serum calcium

Question 2

Number needed to treat

Answer 2

NNT= 1/ARR (absolute risk reduction)

Question 3

anion gap

Answer 3

Na - (Cl + HCO3)

number of unmeasured ions (normal is 10-14)

Question 4

Relative Risk Reduction

Answer 4

RRR= (1-Relative risk)

Question 5

Positive predictive value

Answer 5

PPV= TP/TP+FP

Question 6

negative predictive value

Answer 6

NPV= TN/TN+FN

Question 7

what factors or independent of prevelance in a study?

Answer 7

sensitivity, specificity, likelihood ratios

Question 8

Positive likelihood ratio

Answer 8

LR+= sensitivity/(1-specificity)

Question 9

Negative likelihood ratio

Answer 9

LR- = (1-sensitivity)/specificity