Assignment 1: Intro to Epidemiology I

For Questions 2-7, read the abstract below, and identify the following elements for this study (you don’t need to read the original paper to answer this question):

• Exposure(s) of interest
• Outcome(s) of interest
• Study hypothesis
• Study sample
• Study population
• Target population

Title: Early exposure to house-dust mite and cat allergens and development of childhood asthma: a cohort study

Background: In a prospective birth-cohort study, we assessed the relevance of mite and cat allergen exposure for the development of childhood asthma up to age 7 years.

Methods: Of 1314 newborn infants enrolled in five German cities in 1990, follow-up data at age 7 years were available for 939 children. Assessments included repeated measurement of specific IgE to food and inhalant allergens, measurement of indoor allergen exposure at 6 months, 18 months, and 3 years of age, and yearly interviews by a paediatrician. At age 7 years, pulmonary function was tested and bronchial hyper-responsiveness was measured in 645 children.

Findings: At age 7, the prevalence of wheezing in the past 12 months was 10·0% (94 of 938), and 6·1% (57 of 939) parents reported a doctor’s diagnosis of asthma in their children. Sensitisation to indoor allergens was associated with asthma, wheeze, and increased bronchial responsiveness. However, no relation between early indoor allergen exposure and the prevalence of asthma, wheeze, and bronchial hyper-responsiveness was seen.

Answer the following question:

The following sentence appeared in a recent issue of a prominent medical journal: “Despite the effectiveness of several forms of treatment for heart failure, the prevalence of heart failure continues to rise.”

8. If the “effectiveness” to which the statement refers included a reduced risk of death, would you be surprised to see an increased prevalence of heart failure in relation to more widespread use of these forms of treatment? Explain your reasoning.

Using the information provided below, answer Questions 9 & 10:

• Population of the city of Atlantis on March 30, 2003 is 183,000
• Number of new active cases of TB occurring between January 1 and June 30, 2003 is 26
• Number of active TB cases according to the city register on June 30, 2003 is 264