MI 580: Principles of Epidemiology
Fall 2023 – Homework 1
Due: September 13th at the start of class; 65 points
Instructions: For all calculations, be as explicit as possible by showing the steps to arrive to the
calculations related to the final answer. Showing your work is a component of the homework
grade. Please submit the homework electronically. All calculations can be rounded to one
decimal place.
Question 1 (8 points; 2 points each)
In each example below, indicate which Bradford Hill criteria of causality applies:
a. Individuals who average 1-3 drinks a week have a 5% risk of heart disease. Individuals
who have 3-5 drinks a week have a 10% risk. Individuals who have > 5 drinks a week
have a 15% risk. Biological gradient (dose-response relationship)
b. The association between smoking and lung cancer has been well established in many
studies including men, women, elderly and different racial groups. Consistency
c. An outbreak occurred in a Mexican restaurant. Everyone who got ill ate the salsa before
they got sick. Temporality
d. Heavy smokers have a 20% risk of dying by the age of 75. Heavy coffee drinkers have a
10% risk of dying by the age of 75. The conclusion is that smoking produces a larger risk
of dying compared to coffee drinking. Strength of association
Question 2 (10 points; 2 points each)
Classify each of the following as Primary, Secondary or Tertiary prevention
a. Wearing protective goggles working as a woodcutter: primary prevention
b. Implementing a health promotion program in the general population: primary
prevention
c. Cancer screening: secondary prevention
d. Physical therapy for stroke victims: tertiary prevention
e. Fitness programs for heart attack patients: tertiary prevention
Question 3 (17 points)
You conduct a study to assess the association between Type 2 Diabetes and Chronic Kidney
Disease (CKD). Before testing the association, you understand that you will need to first
present descriptive statistics.
You recruit 330 individuals into your study – 270 have Type 2 Diabetes and 60 are non-diabetic.
60 of the 330 individuals have CKD at the start of the study. You plan to follow the individuals
up for a total of 4 years. However, 40 patients are lost to follow up at the 2 year mark and none
of these patients had developed CKD during the course of the study. The remaining patients
Fall 2023 – Homework 1
Due: September 13th at the start of class; 65 points
Instructions: For all calculations, be as explicit as possible by showing the steps to arrive to the
calculations related to the final answer. Showing your work is a component of the homework
grade. Please submit the homework electronically. All calculations can be rounded to one
decimal place.
Question 1 (8 points; 2 points each)
In each example below, indicate which Bradford Hill criteria of causality applies:
a. Individuals who average 1-3 drinks a week have a 5% risk of heart disease. Individuals
who have 3-5 drinks a week have a 10% risk. Individuals who have > 5 drinks a week
have a 15% risk. Biological gradient (dose-response relationship)
b. The association between smoking and lung cancer has been well established in many
studies including men, women, elderly and different racial groups. Consistency
c. An outbreak occurred in a Mexican restaurant. Everyone who got ill ate the salsa before
they got sick. Temporality
d. Heavy smokers have a 20% risk of dying by the age of 75. Heavy coffee drinkers have a
10% risk of dying by the age of 75. The conclusion is that smoking produces a larger risk
of dying compared to coffee drinking. Strength of association
Question 2 (10 points; 2 points each)
Classify each of the following as Primary, Secondary or Tertiary prevention
a. Wearing protective goggles working as a woodcutter: primary prevention
b. Implementing a health promotion program in the general population: primary
prevention
c. Cancer screening: secondary prevention
d. Physical therapy for stroke victims: tertiary prevention
e. Fitness programs for heart attack patients: tertiary prevention
Question 3 (17 points)
You conduct a study to assess the association between Type 2 Diabetes and Chronic Kidney
Disease (CKD). Before testing the association, you understand that you will need to first
present descriptive statistics.
You recruit 330 individuals into your study – 270 have Type 2 Diabetes and 60 are non-diabetic.
60 of the 330 individuals have CKD at the start of the study. You plan to follow the individuals
up for a total of 4 years. However, 40 patients are lost to follow up at the 2 year mark and none
of these patients had developed CKD during the course of the study. The remaining patients
