Please complete the following for your own review. Be sure to write the correct number that best fits the question and show your work as needed.


The time period between when a disease first occurs, and it is clinically detected is called

which of the following?

1. disease occurrence time

2. time to event

3. induction time

4. latency period


An epidemiologist is studying skin cancer and knows that exposure to the sun is a component cause of the disease. She also knows that the induction time of sun exposure for most people is 20 years. What will occur at the end of 20 years for most people exposed to the sun?

1. people will be diagnosed with skin cancer

2. people will develop the first skin cancer cell

3. people will begin developing symptoms of skin cancer

4. People will die of skin cancer


An epidemiologist is interested in understanding the relationship between sugar intake and hyperactivity among children. He enrolls elementary school children into the study that have not been diagnosed with hyperactivity, then randomly assigned the children to the treatment or control group. For the treatment group, children receive water and a granola bar with their school lunch. He follows the children for one semester then measures the children for symptoms of hyperactivity. What type of study is this?

1. cohort study

2. retrospective cohort study

3. prospective cohort study

4. experimental study


For the study described in the above question, what is the appropriate measure of effect?

1. incidence proportion

2. Incidence rate

3. Relative risk

4. hazard ratio


An epidemiologist hypothesizes that children

who drink dairy milk are more likely to have

ear infections. The epidemiologist has read

the medical literature and understands that

the following can also play a role in causing

ear infections for children: (a) defects of the

Eustachian tube; (b) having the flu; and (c)

exposure to second hand smoke. Which of

the following would NOT be a component in

the causal pie?

1. ear infection

2. exposure to second hand smoke

3. having the flu

4. drinking dairy milk



For a component cause that acts last, the

induction time is which of the following?

1. dependent on the disease

2. short

3. zero

4. dependent on the timing of the other

component causes


Which of the following relative risks (RR)

indicate there is no difference in the

incidence of disease between the exposed

and unexposed groups?

1. RR=1.4

2. RR=0.0

3. RR=1.0

4. RR=0.8


Which of the following is true about


1. it is a science about human disease occurrence

2. it is a science that produces empirical evidence

3. all answers are correct

4. it is an observational science


An epidemiologist is investigating the

following research question: Does increased

alcohol intake increase the risk for liver

cancer? The epidemiologist reported the

following in a published manuscript about the

relationship between alcohol intake and liver

cancer: lowest level of alcohol intake RR=1.0

(ref.); moderate level of alcohol intake

R=1.5; highest level of alcohol intake

RR=2.0. This is an example of which

Bradford Hill’s criteria for causation?

1. experimental evidence

2. biological gradient/dose response

3. plausibility

4. temporality


In which section of a research journal article

should you expect to find a description of

how the exposure was measured?

1. Methods

2. Discussion

3. Introduction

4. Results


The next 1-4 Questions all relate to the

following study. The 2X2 table below

represents the prospective follow-up of 500

premenopausal women for the occurrence of

breast cancer among smokers and

nonsmokers. Women without breast cancer

were enrolled in the study and followed in a

prospective cohort for 12 years. Use the

information from the 2X2 table to answer this

question. What is the risk of breast cancer

among the smokers? Please provide your

final answer followed by your calculation

in the space provided (2 pts.)


Breast cancer No breast cancer


Smoker 79 71



Non-Smoker 99 251



2- Using the information from the 2X2 table in

question 1, how many people smoked?

Show work :



3- Using the information from the 2X2 table in

question 21, what is the relative risk of

smoking and breast cancer? Remember to

round risk to 4 decimal points and the relative

risk to two decimal points.



4- What is one assumption about the relative

risk you calculated in question 3 based on

the follow-up of the cohort?


Chart  Description automatically generated

5- Please refer to FIGURE

In order to answer 5-10. What is the incident

rate of lung cancer for the people exposed to

air pollution? Place your final

answer followed by your calculation in all

questions requiring a calculation.



6- Referring to the Figure , what is the

incident rate of lung cancer for people not

exposed to air pollution?



7- Referring to the Figure , what is the

total person time followed for all of the




8- Convert the incident rate that you calculated

in question 5 for the exposed group to

1,000 person years.


9-What is the incident rate ratio of lung cancer

comparing people exposed to air pollution to

people not exposed to air pollution.


10-State in one sentence the meaning of the

incident rate ratio that your calculated for

question 9


11- Questions 11-12 pertain to the following

study. An epidemiologist has a hypothesis

that meditation will decrease stress among

college students. He enrolls 100 students

that scored high on his stress screening test

and randomly assigns half of the students to

his experimental group to receive lessons on

meditation techniques. The other half of the

students did not receive any intervention and

are called the placebo group. After 6 weeks,

half of the students that received meditation

lessons decreased stress. Ten percent of the

students that did not receive an intervention

decreased stress over the same follow-up

period. Calculate the measure of effect for

this study.

12- Some students receiving meditation lessons

shared what they learned with friend in the

placebo group. The epidemiologist

performed an intent to treat analysis. What

does this mean

Epidemiology Review