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    Question 1 :Give examples of primary, secondary and tertiary prevention that can be used to reduce the damage caused by motor vehicle accidents.

    Question 2 :In a fictitious study, 180 out of 1100 females aged 60 years and over had breast cancer (detected by using Tumour Biopsy or a gold standard test). When these females underwent mammography, 80 of breast cancer patients and 121 healthy females had a positive test result.Please show your answers with ONE decimal place.

    a) Draw a 2×2 table
    b) Calculate and interpret the sensitivity of mammography.
    c) Calculate and interpret the specificity of mammography.
    d) Calculate and interpret the positive predictive value of mammography.
    e) Calculate and interpret the negative predictive value of mammography.

    Question 3 ; Assuming a total number of 200 people who were screened, calculate Positive and Negative predictive values of a; (Hint; first draw and label 2×2 table and you will need two tables, one with 50%prevalence and one with 60% prevalence).

    a) Diagnostic test with Sensitivity 50%, Specificity 50% and prevalence 50%
    b) Diagnostic test withSensitivity 50%, Specificity 50% and prevalence 60%

    Question 4 :A total of 283 university students participated in a hypothetical epidemiological study on cardiovascular disease. The students were recruited to the study in their first year of the undergraduate degree. They were questioned about their lifestyle and other health behaviours, and were also tested for cardiovascular disease. Of the 283 students, five tested positive at their first examination. The students at risk of acquiring cardiovascular disease were followed up for 2 years. During this follow up period, another 14were diagnosed as positive for cardiovascular disease. Unfortunately not all students were followed up for the entire two year study period. Only 160 students were followed up for 18 months, 35 for 14 months, 50 for 6 months, and 15 for 3 months. Calculate the incidence rate of cardiovascular disease for this sample of university students. Express your results per 100,000 person months.

    Question 5 :A city contains 100,000 people (45,000 males and 55,000 females), and 1,000 people die per year (600 males and 400 females). There were 50 cases (40 males and 10 females) of lung cancer per year, of whom 45 died (36 males and 9 females). Calculate the following and express your answers as per 1000:

    a) Crude mortality rate
    b) Sex-specific mortality rate
    c) Cause-specific mortality rate (for lung cancer)
    d) Case fatality rate (i.e. case fatality ratio) for lung cancer.

    Question 6 (2 marks):The population of a city on March 30th 2011 was 183,000. There were 26 new active cases of tuberculosis (TB) occurring between January 1st and June 30th 2011. Total number of active TB cases according to the city register on June 30th, 2011 was 264.

    a) Calculate cumulative incidence of active TB for the six-month period.
    b) Calculate point prevalence of active TB as of 30th June 2011.