In: Statistics and Probability
1· The dentists in a dental clinic would like to determine if there is a difference betweenth0 number of new cavities in people who eat an apple a day and in people who eat less
than one apple a week. They are going to conduct a study with 50 people in each group.
Fifty clinic patients who report that they routinely eat an apple a day and 50 clinic patients who report that they eat less than one apple a week will be identified. The dentists will examine the patients and their records to determine the number of new cavities the patients have had over the past two years. They will then compare the number of new cavities in the two groups.
(a) Why is this an observational study and not an experiment?
(b) Explain the concept of confounding in the context of this study. Include an example of a possible confounding variable.