Section 1 – Paper appraisal

Please read all instructions below and write an appraisal for the following article:

Your appraisal should have the following structure (for more information please see the appraisal lecture slides on the HLTH110 Learn site).

1. Discuss the aims and methods:

a) the research question, and the objective of the study

b) the design of the study (including a selection of study participants and measurement of outcome and exposure)

c) the key result(s)

2. Discuss the internal validity of the study:

a) whether chance could explain the findings

b) whether confounding could explain the findings

c) whether biases could explain the findings

3. Discuss (using the Bradford Hill criteria) causality:

whether the findings suggest a causal relationship

4. Discuss the external validity and the implications

a) Are the study findings generalisability

b) What are the implications

 Four short answer questions 

 Question 1

1. Briefly explain what Figures 1 and 2 show about the number of cancer registrations in New Zealand from 2002-2012

2. Why is it important to use age-standardized rates when examining trends over time?

Question 2

In a cohort study, 10,000 healthy people were interviewed and then followed up for three years. During follow-up, 355 people were newly diagnosed with cardiovascular disease, of which 150 were diagnosed in the first year, 75 in the second year, and 130 in the third year. In the second year of the study, 17 of these people died from cardiovascular disease. There were 200 deaths from other causes during the second year of the study and 95 deaths from other causes in the third year of the study. No participants were lost to follow-up in this study.

1. Calculate the point prevalence of cardiovascular disease in this population at the end of the second year of follow-up. Please explain in words what this result means

2. Please explain why prevalence is not as useful as incidence for investigating possible causes of illness.

You are trying to investigate if a higher amount of fast-food advertisements around a child’s house relates to a higher risk of developing obesity. You are involved in a longitudinal/cohort study in Christchurch which follows people over time to examine the association between the fast-food advertisements in a neighborhood (i.e. around a home) when a child is age 10 years and obesity at 18 years (8 years follow up). It is plausible that children who have more fast-food advertisements around their home at age 10 have a higher risk of obesity at age 18 years.

Table 

1. Please calculate the odds ratio (show your workings) and then describe the association between fast-food advertisements and obesity?

2. Please explain what you understand by a 95% confidence interval. The confidence interval for the above association for fast-food advertisement at age 10 and obesity at age 18 is 3.90 to 4.10. Explain what this means?

Question 4

You wish to carry out a randomized controlled trial to find out whether e-cigarettes (vaping) can help regular smokers of tobacco cigarettes to quit.

1. Describe briefly how a randomized controlled trial could be used to investigate whether there is an association between the use of e-cigarettes and quitting

2. Discuss the advantages and disadvantages of a randomized controlled trial to answer this research question