Reference no: EM133136154 , Length: word count:1500

7312MED Epidemiology: Principles And practice - Griffith University

ASSIGNMENT 1 Measures of Disease Frequency and Association, Types of Epi Study Design

Question 1
Diabetes is one of the fastest growing chronic diseases in Australia. The following table shows the total new cases of diabetes from January 2010 to December 2012 in Queensland andNorthern Territory and the population data of the two states from Census survey in 2011.

Table 1 Numbers of type II diabetics and total populations by age in Queensland and Northern Territory

(a) Which measure of disease frequency (prevalence, cumulative incidence, incidence density or estimated incidence rate) is most suitable in this example? Provide two reasons to justify your answer.
(b) Calculate the overall disease occurrence (using a crude measure which was nominated in the previous question) of type II diabetes in each of the two states. Please include a population multiplier of per 10,000in your calculations and identify which state had a higher crude rate of type II diabetes.
(c) What were the risks (ie using a measure of disease frequency) of developing type II diabetes in different age groups in each of the two states? How does the risk of developing diabetes vary by age in each state? (Usean appropriate measure of association to quantify the variation). Based on your results, discuss whether or not age is a risk factor of type II diabetes inthe two states.
(d) Compare the age structures in the populations of Queensland and Northern Territory (calculate the percentage of each age group). Is the comparison of crude occurrence valid in consideration of the population structures in the two states? Why or Why not?
(e) Use Australia's population as the standard population to compute the direct standardised rates (age adjusted rates) of type II diabetes in Queensland and in Northern Territory. Compare the results of crude and standardised rates between the two states and interpret your findings.

Question 2
An epidemiologist investigated a Covid-19 cluster at an aged care residence. The following figure presents the findings of the investigation. Assume that the total observation period was eight weeks. Please use per 100 people as the population multiplier for this question.

(a) What is the point prevalence at the beginning of Week 5?
(b) What is the cumulative incidence (incidence proportion) from the beginning of Week 5 to the end of Week 8?
(c) What is the incidence rate (incidence density) of Covid-19 during the 8-weekinvestigation?
(d) What is the risk of dying (mortality)due to Covid-19 from the beginning of Week 5 to the end of Week 8?

Question 3
A recent study assessed whether or not having hepatitis C virus (HCV) infection would increase the risk of B-cell non-Hodgkin lymphomas (B-NHL). The patients newly diagnosed with B-NHL were identified in the hematology department wards of 10 cities in Country A. The control group consisted of patients admitted to other departments of the same hospitals. The table below presents the numbers of cases and controls as well as the numbers of HCV tests results by age.

Table 3 Numbers of B-NHL outcome status and HCV result by age

(a) What was the actual study design? Under similar research conditions, which type of study design would be most feasible? (provide reasoning for your choice)
(b) Calculate the appropriate measure to determine the strength of association between HCV and B-NHL regardless of the effect of age. Interpret your result briefly. (HINT: draw a 2x2 table according to the participants' outcome and exposure status)
(c) What percentage of B-NHL among patients with HCV positives could have been potentially prevented if they were not HCV positives? What is this measure called? Calculate the measure and explain your result briefly.

Question 4
Search data of "Mortality and Global Health Estimates" (using data in 2016, except life expectancy and healthy life expectancy data) for 3 selected countries: Australia, Brazil and Kenyafrom WHO's Global Health Observatory website WHO's Global Health Observatory website

(a) Compare the population and crude mortality data (Items 1-3) of the three selected countries, and summarise your comparison results briefly (Word limit: 150 words). Considering the population proportions presented in the table, is crude mortality rate a useful measure for comparing the overall public health status among the three countries? Why or why not? (Word limit: 200 words).

(b) In comparison of the life expectancy data between the selected countries (Items 7-8), why do the total years of life expectancy estimated at birth differ from the lengths of life expectancy estimated at age 60? Also, why are the lengths of healthy life expectancy at birth not the same as the lengths of life expectancy at birth? (Word limit: 200 words).

(c) According to the completed Table 4, compare the population health data (Items 3-8) and conclude the general levels of public health among the three countries (Word limit: 200 words).

Attachment:- Epidemiology.rar