Flexibility and Consistency in Long-Term Care Rostering

Problem definition: We consider the rostering decisions—that is, the assignment of workers scheduled for a shift to units—of a long-term care facility. The facility’s objective is to minimize the monthly inconsistency level, a widely promoted quality metric representing the number of different caregivers working in each unit over one month. Methodology/results: We introduce simple rostering heuristics that prioritize either part-time or full-time workers and present a stochastic model of the repeated rostering problem to compare the performance of different strategies analytically. Our analysis shows that in order to minimize the inconsistency level, part-time workers should receive higher priority than full-time workers for assignment to their home units. We also establish an analytical upper bound for a threshold on the time horizon above which a policy giving assignment priority to part-time workers is guaranteed to outperform one giving priority to full-time workers. Using data from more than 15,000 shifts worked by nursing assistants at three nursing homes, we compare the actual rosters to the hindsight optimal consistency-maximizing schedules, demonstrating a significant opportunity for improvement. We then compare the performance of our rostering heuristics via trace-based simulation of the historical schedules. This reinforces the superiority of prioritizing part-time workers, yielding reductions in the inconsistency level between 20% and 30% compared with the historical rosters. Managerial implications: Contrary to popular guidance, our results show that managers should focus on part-time workers and assign them as consistently as possible. Even if some full-time workers are always assigned to their home units (because of preferences or work rules), assignment flexibility among the remaining full-time workers still enables significant improvements in the consistency of care. This flexibility among full-time workers helps because their higher work frequency tends to make a reassignment away from their home unit contribute less to inconsistency, because they are able to work multiple shifts in these nonhome units. Supplemental Material: The e-companion is available at https://doi.org/10.1287/msom.2022.1174 .