What is the response (Y) of interest and how is it measured? We are interested in understanding the change in the appointment backlogs from May 1, 2015 to May 1, 2016. The column Backlog Difference contains this change. It is a continuous variable.

Are predictor variables mentioned in the problem statement? If so, how many and what are their measurement levels? The research question asks if there has been a change in the backlog over a year. The predictor is time, a nominal variable, measured at two points in time.

What are you being asked to deliver? A data description, an interval estimate, an answer to a question, or a predictive model? We are being asked to answer a question regarding the change in backlog over a year. A test of hypothesis will establish if the average change in backlog is statistically significant.