Biostats and Ethics

Question 1

RR and OR are important equations

Answer 1

Know them

Question 2

2 X 2 table for risk of disease?

Answer 2

Disease comes out on top. Then do like so

A B
C D

Question 3

What is relative risk?

Answer 3

Risk of getting disease in exposed population

Compared to

Risk of getting disease in unexposed

Question 4

Whats odds ratio?

Answer 4

Odds ratio is same as relative risk if prevalence is is SUPER LOW!!! (basically able to take out A and C in dividing)

A/B / C/d

Question 5

Number needed to treat calculation?

Answer 5

1/ absolute risk reduction

So 1/( C/(C+D) - A/(A+B) )

Question 6

Positive likelihood ratio is what?

Answer 6

Sensitivity / (1-specificity)

Or sensitivity/false positive ratio

Question 7

What is negative likelihood ratio?

Answer 7

(1-sensitivity)/specificity

Or false negative rate/specificity

Question 8

Type 1 error is what?

Answer 8

Null hypothesis rejected even thought its true

Type 1 FIRST TO LIE and say there is affect where there isn’t!

Question 9

Confidence Interval calculations?

Answer 9

CI = Range from mean -Z(SEM) to mean +Z(SEM)

90% z is about 1.6
95% Z is about 2, 99 Z is about 2.6

Question 10

Z for 90, 95, 99% CI?

Answer 10

1.6, 2, 2.6

mean +/- Z SEM