Multi-objective analysis of hospital delivery systems

Automation introduction in hospital applications has become increasingly important in recent years. Delivery, transportation and distribution services are examples of critical operations that can be automated. This paper examines clinical laboratory and pharmacy deliveries in middle to large size hospitals, in order to evaluate whether or not a fleet of mobile robots can replace a traditional human-based delivery system. The complexity of the problem derives from its multi-objective character, since several, often contrasting factors must be taken under consideration. The problem has common characteristics with transportation system design and automation introduction evaluation in manufacturing. The Analytic Hierarchy Process was used to build a decision problem that synthesized economic and technical performance as well as social, human and environmental factors. The technical performance measures were assessed through computer simulation. This research provides a methodology to approach automation introduction evaluation in a hospital environment. The final results enable a better understanding of the delivery and transportation requirements of middle to large size hospitals and how a fleet of mobile robots can meet these requirements. We applied our methodology to the University of Virginia Health Science Center. We show with a high overall confidence that a fleet of mobile robots can achieve better final results than a human-based transportation system according to a representative preference structure formulated by a hospital manager. An ANOVA analysis indicates that the final results were not excessively dependent on the input data of the simulation model. In addition, a sensitivity analysis indicated that the results are stable with respect to variations in the decision maker's preference structure. (C) 2001 Elsevier Science Ltd. All rights reserved.