MPH5040/6040 Introductory Epidemiology - Assessment 4: Critical Appraisal

Critically appraise the article:

Frei P, Poulsen AH, Johansen C, Olsen JH, Steding-Jessen M, Schuz J. Use of mobile phones and risk of brain tumours: update of Danish cohort study. BMJ 2011;343:d6387. doi: 10.1136/bmj.d6387 The paper can be accessed via https://www.bmj.com/content/343/bmj.d6387.long

Please read the paper and address the following tasks:

1. Specify the aim and the hypothesis (both null and alternative) of the study (5 marks)
2. Specify the type of the study (study design) (2 marks)
3. Why did the authors conduct the study on use of mobile phones and risk of brain tumours i.e. what is the rationale for the study? (2 marks)
4. What are the outcomes and how are they measured? (3 marks)
5. What are the exposures and how are they measured? (3 marks)
6. Considering the widespread use of mobile phones, the general public is very interested in the results of this study. In no more than 100 words, summarise the key points of the research described in the paper by Frei et al. 2011 using language that a member of general public could be expected to understand. (10 marks; 100 words max)
7. Discuss on whether the findings of the paper be explained by chance. (15 marks)
8. Discuss on whether the findings of the paper be explained by selection bias or information (measurement) bias. (20 marks)
9. Discuss on whether the findings of the paper be explained by confounding. (15 marks)
10. Assuming further research is needed to confirm the major findings of the paper, describe what would be the best study design and why? Which study designs are unlikely to add further information and why? (20 marks)
11. Discuss external validity of the study. (5 marks)