This paper circulates around the core theme of a) In this case-control study, it is …… …………to calculate the risk of pancreatic cancer among coffee drinkers, together with its essential aspects. It has been reviewed and purchased by the majority of students thus, this paper is rated 4.8 out of 5 points by the students. In addition to this, the price of this paper commences from £ 99. To get this paper written from the scratch, order this assignment now. 100% confidential, 100% plagiarism-free.
i) A classic case-control study was conducted in 1966 to compare the coffee drinking habits of pancreatic cancer patients with the coffee drinking habits of other patients. [2 marks]
a) In this case-control study, it is …… …………to calculate the risk of pancreatic cancer among coffee drinkers, and thus, the appropriate measure of association is the ……….
Choices: Not possible, odds ratio, possible, risk ratio
ii) Let’s consider the data below from this classic case-control study to assess the relationship between coffee drinking and pancreatic cancer. [1+1+2= 4 marks]
Coffee drinker Non-coffee drinker Total
Cases 1350 150 1500
Controls 1260 240 1500
Total 3000
a) What is the probability of being a coffee drinker among cases?
b) What is the Odds of coffee drinking among control?
c) What is the odds ratio?
Question 2 – 6 marks
The association between decreased duration of exercise and incidence of coronary heart disease (CHD) was studied among men enrolled in a cohort study. Among men who reported exercising >2 - 3 hours per week there were 541 incident cases of CHD during 451,393 person-years of follow-up. Among those who exercised 1 - 2 hours per week there were 267 cases in 175,629 person-years, among those who exercised less than one hour per week there were 67 cases during 30,115 person-years of follow-up.
i) Calculate the incidence of CHD among [4 marks]
a) Men who reported exercising >2-3 hours per week.
b) Men who reported exercising 1 - 2 hours per week.
c) Men who reported exercising less than one hour per week.
d) All Men.
ii) How strong is the association between duration of exercise and the incidence of CHD? [2 marks]
Question 3 – 3 marks
Imagine a research team wanted to estimate the prevalence of vegetarianism in the community by means of a short questionnaire distributed with a women’s health magazine. Would this give an accurate picture of the percentage of people who were vegetarians? Please explain briefly.
Question 4 – 12 marks
In 1976, the Nurses’ Health Study surveyed 121,700 US female nurses aged 30-55. Information was updated every two (2) years. On the 1986 questionnaire, snoring was surveyed. The investigators wished to relate this to the development of type II diabetes. They had 10 year follow-up + sufficient information for analysis on ~67,000 women.
a) What sort of study is this? [1 mark]
b) Snoring was reported as none, occasional or regular:
of 6,000 regular snorers, 400 developed diabetes
of 43,000 occasional snorers, 1300 developed diabetes
of 18,000 non-snorers, 200 developed diabetes
Draw the 2 x 3 table that summarises the data [2 marks]
c) Calculate the absolute risk of diabetes over the 10 year follow-up period for non-snorers, occasional snorers and regular snorers. [3 marks]
d) Calculate the relative risk of diabetes over the 10 year follow-up period for occasional snorers relative to non-snorers, and regular snorers relative to nonsnorers. [2 marks]
e) The authors depended on self-reported diagnosis of type II diabetes. This might lead to: [1mark]
i) selection bias ii) misclassification bias iii) Berkson bias iv) Neyman bias
v) confounding bias
f) Speculate on the possible direction of the bias created by using self-reported diagnosis of type II diabetes [2 marks]
Being a good epidemiologist you question the association between snoring + diabetes. You know that obesity could the underlying cause of snoring as well as diabetes, and that the link between snoring and diabetes might therefore be spurious. [1 marks]
The proper epidemiological way for phrasing this is:
i) snoring is a potential confounder in the causative association between obesity and diabetes
ii) obesity is a potential confounder in the causative association between snoring + diabetes
