Question 22

A confidence interval for the stratum-specific odds-ratio for the association between physical activity and CHD in those with a high-fat/moderate diet is calculated as (0.90-1.70). This best interpretation of this is:

Group of answer choices

A. There is not a statistically significant association between diet and CHD in people who exercise

B. There is not a statistically significant association between exercise and CHD in those who consume a high fat/moderate diet

C. Diet is not associated with physical activity

D. Diet is an effect modifier

E. There is a statistically significant positive association between exercise and CHD in those who consume a high/moderate fat diet

Question 23

A new treatment is developed for a disease, that prevents death, but does not result in recovery from the disease. Which of the following will occur?

Group of answer choices

A. Incidence will increase

B. Incidence will decrease

C. Prevalence will increase

D. Prevalence will decrease

E. Mortality will increase

The following information is to be used to answer questions 24-26:

A survey was conducted among women to assess the relationship between anxiety and smoking. One hundred and sixty women were asked about their anxiety and smoking habits, and classified according to anxiety level (treated as a dichotomous variable: high anxiety/low anxiety) and smoking status.

	Smoker	Non-smoker	Total
High Anxiety	76	24	100
Low Anxiety	22	38	60
Total	98	62	160

Flag question: Question 24Question 242 pts

What is the value of the prevalence ratio?

Group of answer choices

A. It is not appropriate to calculate this measure

B. 2.1

C. 1.9

D. 0.4

E. 5.5

Question 25

What can be concluded based on the value of the prevalence ratio?

Group of answer choices

A. Anxiety is positively correlated with smoking

B. Smoking is a risk factor for anxiety

C. Anxiety is negatively correlated with smoking

D. There is no association between anxiety and smoking

Question 26

Based on the data from this cross-sectional survey, what is the relative risk of smoking among people with anxiety?

Group of answer choices

A. 0.4

B. 40%

C. 2.1

D. 5.5

E. It is not appropriate to calculate a relative risk in this study

Question 27

A process by which the investigator assigns the subject to either the treatment or comparison group to improve the likelihood that the two groups will be comparable with regard to known and unknown confounding factors is known as:

Group of answer choices

A. Nonresponse bias

B. Blinding

C. Randomization

D. Stratification

Question 28

A case-control design:

Group of answer choices

A. Is often the most expensive design option available

B. May be less time consuming than other designs

C. Is good to study outcomes that are rare

D. Is associated with a long follow-up period

B and C

Question 29

True or False: A clear temporal relationship between exposure and disease is an advantage of cross sectional studies.

Group of answer choices

True

False

Question 30

True or False: Internal validity implies the ability to generalize beyond a set of observations to some universal statement.

Group of answer choices

True

False