Comparing measures of disease

Question 1

Magnitude of effect in measurement dara

Answer 1

difference in means – how big is the difference in the means for groups with or without a particular risk factor?

Question 2

Magnitude of effect in count data

Answer 2

ratio or differences in incidence, prevalence, or odds (risk ratio, prevalence ratio, odd ratio, risk difference, prevalence difference, attributable fraction)

Question 3

Significance of effect

measurement

Answer 3

P value
* determines whether the difference seen between groups occurs by chance or is signficant

Question 4

What is the standard P-value used to determine significance?

Answer 4

p <0.05 or p < 0.01

Question 5

Precision of estimate

Answer 5

certainty of the size of the difference between means (confidence intervals)

Question 6

Risk ratio

Answer 6

ratio of incidence rates (how many tmes more likely are those with factor to develop the disease)

Question 7

Risk Difference

attributale risk

Answer 7

Difference in incidence rates (how many more individuals out of 100 with the risk factor are going to get sick compared to 100 individuals without the risk factor)

Question 8

Attributable Fraction

Answer 8

Difference in incidence rates due to risk factor (proportion of all cases that can be attributed to a specific risk factor)

Question 9

Prevalence Ratio

Answer 9

ratio of prevalence rates

Question 10

Prevalence difference

Answer 10

difference in prevalence rates

Question 11

Odds ratio

Answer 11

estimates risk ratio for a **case-control study **