Use this case study in combination with the Case Study 2 – AA Spouse Depression.xlsx
A study in 2005 was conducted to determine whether there was a difference in the depression of women and men who were participating in Alcoholics Anonymous program as well as whether the presence of their spouses at the meetings had a relationship on their depression score.
One-hundred-ninety-six men and women participated in the study, and their depression scores after 30 days and 180 days were captured using a depression inventory on which lower scores represented lesser depression. The score range on the instrument is 3 to 24.
The data are contained in the file “Case Study 2 – AA Spouse Depression.csv.” You will perform a set of analyses on the data with the file, and then interpret the results to indicate your findings. The column Spouse Present indicates whether the participant was enrolled in an AA program that encouraged spouses to attend (1) or did not allow others except the participant to attend meetings (called closed meetings). In addition, the age and urban or rural residence of the participant is shown. All participants are married whether their spouse attended or not.
1) Prepare a table of the data using the following template.
Sex Mean Depression Score, 30 days (sd) Mean Depression Score, 180 days (sd) Mean Age, (sd)
Male
Attended with spouse
Attended without spouse
Female
Attended with spouse
Attended without spouse
Based on this information alone, what conclusions can you state?
2) Which group had the most variation in depression scores at 30 days, men or women? Did this change at 180 days?
3) You have elected to run all statistical tests in this case study at α = 0.05. What does that mean to the layperson in terms of the research question, “Is there a difference in depression scores between those attending AA meetings with their spouses and those attending AA meetings without their spouses?”
4) Determine whether there was a statistically significant difference between depression scores at 180 days between the following groups:
a. Men and women
b. Those attending with their spouses and those attending without their spouses
c. Those living in rural areas and those living in urban areas
5) While we would not ordinarily conduct the tests in (4) separately like you were asked to do (because of the experiment-wise error), we did, in fact, conduct 3 separate statistical tests. Now, we would like to consider the omnibus ANOVA test to conduct our analysis.
Using the table below as a guide, conduct a two-way ANOVA to determine whether there is an interaction effect between having a spouse present and the sex of the participant. Of course, the 180 day depression score is the dependent variable. If there is an interaction, then discuss what this means. Also, discuss the main effects of gender and spouse being present or not.
Male Spouse Present Spouse Absent
Female
Repeat the ANOVA; but, this time use Spouse Present/Absent and Rural/Urban Location as the independent variables. Interpret your results.