A psychologist at a private mental health facility was asked to determine whether there was a clear difference in the length of stay for patients with different categories of diagnosis. Looking at the last seven patients in each of the three major categories, the results (in terms of weeks of stay) were as follows.Using the data below, test whether the length of stay for patients varies based on the category of diagnosis.

Numbers:

Affective Disorders	Cognitive Disorders	Drug-related Conditions
7	12	8
6	8	10
5	9	12
6	11	10
9	11	9
5	10	11
6	9	12

Questions:

1. What is a potential confounding variable in this scenario? Explain your rationale.
2. Present the results using APA format. This includes a full write-up to include a complete statistical notation as shown in the weekly presentations. The write-up also needs interpretation. If significant, state how. If it is not significant, what does that mean in layman's terms?
3. In this specific scenario, what is the independent variable? Is it between or within-subjects? How many levels does it have, and what are they?