Biostatsssss

Question 1

How do you calculate number needed to treat?

Answer 1

1/ARR

Question 2

How do you calculate Number needed to harm?

Answer 2

1/AR

Question 3

How do you calulate Relative Risk Reduction?

Answer 3

1-RR

Question 4

What is Berkson bias?

Answer 4

Hospital patients only

Question 5

What is the Hawthorne effect?

Answer 5

Groups who know they are being studied behave differently

Question 6

How do you calculate SEM?

Answer 6

SD / sq rt. n, n=sample size

Question 7

% of population within 1 SD, 2 SD and 3 SD

Answer 7

1 = 68%, 2 = 95%, 3 = 99.7%

Question 8

How do you calculate confidence interval?

Answer 8

Z[SD/sq. rt. (n)]

Question 9

What is the Z value for a 95% CI?

Answer 9

1.96

Question 10

What is the Z value for a 99% CI?

Answer 10

2.58

Question 11

What value is usually reported for correlation?

Answer 11

r^2 = coefficient of determination

Question 12

What is considered a good Apgar score (and how is it determined)?

Answer 12

> /= 7 : based on baby’s appearance, pulse, grimace, activity, and respiraiton.