Association Misc.
Ratio and Difference
Relative Risk
Odds Ratio
Misc. Calculations
100
Absolute risk is used to calculate association. True or False?
False, absolute risk does not take into consideration the risk of disease in nonexposed individuals.
100
Ratio of risk and difference in risk are not calculations used to determine association. True or False?
False
100
Relative risk calculations can be used in cohort and case-control studies. True or False?
True
100
The ratio of the number of the number of ways an event can occur to the number of ways that event cannot occur.
Odds
100
What is the equation for relative risk?
Incidence in exposed/Incidence in nonexposed
200
Name two of the methods used for calculating association.
Ratio of rates, difference in rates, relative risk, odds ratio. All accepted
200
Difference and Ratio calculations do not determine association. True or False
False
200
What would it mean if the calculated relative risk were equal to 1?
A relative risk equal to 1 would mean the risk in the exposed and the risk in the nonexposed are equal. Therefore, no evidence exists for any increased risk and does not show association.
200
If the exposure is negatively related to the disease the odds ratio will be _______. A. Greater than 1 B. Less than 1 C. Equal to 1
B. Less than 1
200
If the disease risk in an exposed population is 8 and the disease risk in a nonexposed population is 5 what is the difference in the risks?
3
300
Define relative risk.
Relative risk is the ratio of the risk of disease in exposed individuals to the risk of disease in nonexposed individuals.
300
If you were to divide the disease risk in the exposed by the disease risk in the nonexposed you would be calculating _____.
Ratio of risks (Relative risk is acceptable)
300
If the risk in exposed persons is less than the risk of nonexposedpersons the relative risk will be ______. A. Greater than 1 B. Less than 1 C. Equal to 1
B. Less than 1
300
In an odds ratio equation (1-P) in the denominator is used to represent ______.
The probability of losing
300
In a hypothetical study, there were 30 people exposed to a leather who developed a disease and 20 people exposed to a leather who did not develop a disease. What are the odds of the disease developing in an individual exposed to leather?
Odds: .6
400
In a case-control study, relative risk can be calculated directly. True or False? Explain your answer.
False, a case-control study starts with diseased people and nondiseased people. The incidence of the exposed and nonexposed is not given.
400
The disease risk in exposed subtracted by the disease risk in nonexposed is ______.
The difference in risks.
400
Given the number people who developed a disease and the number of people who did not develop the disease in an exposed population is it possible to calculate relative risk? Explain your answer.
No, the numbers of a nonexposed population would be necessary to calcuate this.
400
How is the odds ratio defined in a cohort study?
The ratio of the odds of the development of a disease in exposed persons to the odds of development of disease in nonexposed persons.
400
Use the following data from a hypothetical disease to calculate the relative risk and the odds ratio. Develop Disease Do Not Develop Exposed 100 4,900 Nonexposed 50 4,950
Relative Risk: 2 Odds Ratio: 2.02
500
When is the odds ratio obtained in a case-control study a good approximation of the relative risk in the population? (There are 3 conditions to be met.)
1. When cases are representative of all those with the disease in the population from which they were drawn. 2. When the controls are representative of all those without the disease in the population from which they were drawn. 3. When the disease being studied does nto occur frequently.
500
In a hypothetical study, the incidence of pancreatic cancer in people exposed to Mcdonalds food is 50% and the incidence of pancreatic cancer in those who were not exposed to Mcdonalds is 25%. Calculate the Difference in the risks and the Ratio of the risks.
Ratio- 2.0 Difference- 25%
500
In a hypothetical cohort study, of the people exposed to coal mines, 35 of them develop lung cancer and 300 do not. Of those who were not exposed to coal mines, 10 of of them develop lung cancer and 800 do not. Calculate the relative risk of this study. What is the significance of the answer?
Relative Risk= 8.352 The relative risk is significantly greater than 1. This is evidence of a positive association, and may be causal.
500
In a hypothetical study, out of 600 people who were exposed to a pig got the flu. Out of the 1200 people who were not exposed to a pig 900 of them did not get the flu. Calculate the odds ratio for the study.
3
500
Given the following information on a hypothetical disease study, calculate the odds ratio and relative risk. Explain the significance of these numbers. Developed Did not Develop Exposed individuals: 100 100 Not Exposed: 50 150
Odds Ratio: 3 Because the relative risk is greater than 1 the disease is positively related with exposure, in other words, there is reason to believe exposure is associated with the disease. Relative Risk: 2 Because the relative risk is greater than 1 the disease is positively related with exposure, in other words, there is reason to believe exposure is associated with the disease.
M
e
n
u