Question

Need assistance with this assignment.

Read the Boffetta et al. (2010) article. Identify any potential threats to internal or external validity in the article. Do you notice any potential problems with the conclusions?

Answer 1

Note: This response is in UK English, please paste the response to MS Word and you should be able to spot discrepancies easily. You may elaborate the answer based on personal views or your classwork if necessary.

(Answer) This study by Boffetta et al. is about probable carcinogens in vegetables and fruits. In order to study the link between the consumption of certain fruits and vegetables with cancer and death rate, the researchers collected data of the populace of a particular area. The researchers collected data about the history cancer patients, deaths and consumption/purchase of fruits and vegetables.

From what can be gathered by reading the article, the researchers have used a correlation study to determine a causal relationship. There are pros and cons to this study in terms of validity. Firstly, when it comes to correlation study, one must accommodate that fact that there could be a confounding variable. For instance, People who eat pizza from an expensive restaurant “A” had a lesser chance of heart disease than people who ate from a cheaper pizza restaurant “B.” However, the confounding variable “C” is that the richer people could afford to spend on an organic diet that was the actual cause of the lower risk of heart disease. Therefore the issue of the research methodology is the problem of internal validity.

The issue with external validity is that the study relies more on historic data of population affliction and lifestyle in terms of food and not much of actual biological research. This study does contain a few scientific pursuits. However, they seem to be inconclusive in certain areas. Analysis of the gene structure of the fruits and vegetables on a cellular level would have to be conducted for a proper external validity of this study and not a mere census.

The problem with the discussion (there is no concrete conclusion paragraph in this study), is that the researcher only talks about data derived from census and there is hardly any scientific discussion. Since fruits and vegetable are not the only things that people consume and that humans are exposed to several other environmental factors, it is not possible to confirm the hypothesis with validity.