PUB210 Concepts Of Epidemiology - Assessment Task 2PUB210 Concepts Of Epidemiology - Assessment Task 2

A large hypothetical study assessed the association between average daily hours using electronic media (i.e. ‘screen-time’) at eight to ten years of age and the incidence of sight problems as a teenager. In children for whom low levels of screen-time were reported, there were 1,318 incident cases of sight problems during 280,364 person-years of follow-up. In children with intermediate levels of screen-time there were 3,070 cases in 436,372 person-years, and in children with the highest levels of screen-time, there were 4,104 cases in 407,193 person-years of follow-up.

1. Calculate the incidence rate of sight problems as a teenager overall and among children who had each level of screen-time as an eight to ten year-old child. (2 marks)
2. How strong is the association between screen-time as an eight to ten year-old child and incidence of sight problems as a teenager? [Note: Assume that the results cannot reasonably be explained by the alternative explanations of bias, confounding or chance.] (2 marks)
3. What proportion of sight problems could theoretically be prevented if all children had low levels of average daily screen time? (2 marks)