Tasmanian researchers conducted a case –control study to investigate the effect of dietary fat intake on melanoma (Skin Cancer). They hypothesised that people whose dietary fat intake is low will be more susceptible to skin cancer. The study compared 500 cases of melanoma with 500 controls. The controls were randomly selected from the state’s electoral roll. The researchers categorised the dietary fat intake into three categories High, Moderate and Low. They found that among skin cancer patients 150 were classified at the low and 80 at the high dietary fat intake whereas among control 130 were at the low and 100 were at the high.
a) Build a table to summarise the data above which will help you estimate the association between dietary fat intake and Skin cancer [4 points]
b) Calculate the relative risk (RR) of high fat intake versus low fat intake and the RR of medium to high fat intake in relation to the development of melanoma, what type of RR are these and explain in words the meaning of what you found [4 points].
c) Calculate the percent attributable risk due to exposure to low-dietary fat intake on Melanoma and explain in one or two sentences the meaning of your findings [4 points]
d) Calculated the population attributable risk of low-fat intake on melanoma and explain in words the meaning of such finding [4 points]
e) What do you think about the conclusions of the PAR regarding exposure to low fat diet to reduce melanoma? (no more than 3-4 sentences) [4 points}