Assessing Confounding in Multivariate Regression

1) Middleton and colleagues (2010) conducted a study to look at the relationship of physical activity over the life course (i.e., at different ages) and the development of late-life cognitive impairment. They analyzed cross-sectional data using logistic regression, and reported the following results:

Describe the results of the study as represented in the table above. Be sure to address main effects of the different subgroups as well as any evidence of effect modification. Don’t forget to address the statistical significance of the findings.