Why does the 2nd shift (afternoon staffing) analysis not consider variation in workload by day of the week?
There are two reasons why this is so. First, when variation by day of the week is addressed by the 1st shift (OR efficiency) analysis (click here for lecture or click here for review article), two factors are modeled: service (i.e., unit of OR allocation) and day of the week. When variation by day of the week is addressed by the 2nd shift (afternoon staffing) analysis, there are three factors: specialty team, day of the week, and time of the day. The 1st shift analysis does not need to consider time of the day as an independent variable, because OR time is allocated and cases are scheduled based on OR efficiency, thereby relating the dependent variable of workload with the time of the day at which cases are performed. For example, if there were 10 hours of cases, the 1st shift (OR efficiency) analysis would assume that the day would end at 5 PM, whereas the 2nd shift (afternoon staffing) analysis would make no assumption about when the workload would end. The result is that there is mo
