A 5-year-old child frequently gets skin rashes, and the mother has been told by her family doctor that the problem is due to “something” the child eats. The doctor suggests that she “watch carefully” what the child eats. The mother decides to approach this problem by recording each day whether the child has a rash and what the child ate the day before. She hopes to find some relationship between eating a particular food and the presence or absence of the rash. Although this approach might help discover a relationship between eating certain foods and the appearance of the rash, a better approach might be one based on the logic and procedures associated with single-case designs. Explain how the mother might use such an alternative approach. Be specific and point to possible problems that may arise in this application of behavioral methodology.