An epidemiologist hypothesizes that exposure to a chemical is associated with a
ID: 3041795 • Letter: A
Question
An epidemiologist hypothesizes that exposure to a chemical is associated with a neurological disease. To study whether there is an association, the epidemiologist designs and conducts a prospective cohort research study. First, she recruits and enrolls into her study 5,000 people who do not have the neurological disease. During a 4-year follow-up period, the researcher observes the study population to assess exposure and finds that 1,000 participants work in industries where this chemical is used and the other 4,000 participants work in industries where this chemical is not used. She assumes that those who work with the chemical are exposed, and those who do not work with the chemical are unexposed. At the end of the follow-up period, there are 250 cases of the disease in her study population. Of those 250 participants, 50 worked in industries where the chemical was used during the study period, and 200 did not. Based on these results, please answer
the following questions, clearly showing how you arrived at your answers.
(20 points total) An epidemiologist hypothesizes that exposure to a chemical is associated with a neurological disease. To study whether there is an association, the epidemiologist designs and conducts a prospective cohort research study. First, she recruits and enrolls into her study 5,000 people who do not have the neurological disease. During a 4-year follow-up period, the researcher observes the study population to assess exposure and finds that 1,000 participants work in industries where this chemical is used and the other 4,000 participants work in industries where this chemical is not used. She assumes that those who work with the chemical are exposed, and those who do not work with the chemical are unexposed. At the end of the follow-up period, there are 250 cases of the disease in her study population. Of those 250 participants, 50 worked in industries where the chemical was used during the study period, and 200 did not. Based on these results, please answer the following questions, clearly showing how you arrived at your answers. A. (5 points) What is the risk of disease among unexposed workers? B. (5 points) What is the risk of disease among exposed workers? C. (5 points) What is the relative risk? D. (5 points) Based on these results, what would the epidemiologist conclude about the relationship between exposure to the chemical and risk of this disease?Explanation / Answer
a) Risk amongst unexposed = 200/4000=0.05
b)Risk amongst exposed = 50/1000=0.05
c)Relative risk=0.05/0.05=1
d) Exposure to chemical and risk of the disease has no correlation with each other.