Statistics

Question 1

What is the relationship between NNT (number needed to treat) and risk reduction?

Answer 1

NNT = 1/ARR

Question 2

What is the relationship of positive likliehood ratio in terms of the 2x2 box? In terms of sensitivity and specificity?

Answer 2

LR(+) = TP/FP

LR (+) = sens/(1-spec)

Question 3

What is the relationship of negative likliehood ratio in terms of the 2x2 box?

Answer 3

LR (-) = TN/FN

LR (-) = (1-sens)/spec