Courtesy of UCLA's Statistical Consulting Group, this presentation walks folks through some potential points of confusion that can quickly complicate logistic regression results. Step-by-step illustrations assist the explanation. A brief description of the site's motivation follows.
"... But in logistic regression interaction is a more complex concept. Researchers need to decide on how to conceptualize the interaction. Is the interaction to be conceptualized in terms of log odds (logits) or odds ratios or probability? This decision can make a big difference. An interaction that is significant in log odds may not be significant in terms of difference in differences for probability. Or vice versa."