An application of variable neighbourhood search to hospital call scheduling of infant formula promotion

In the infant formula industry, products must rely on the prescription or recommendation from healthcare physicians (HCPs). Therefore, it is the most important activity in sales promotion to call on the identified HCPs in the prospected hospitals by the territory promotional sales representatives (PSRs). The PSRs have to establish their monthly hospital call schedule according to several constraints. In this paper, we investigate the hospital call scheduling of PSRs, a real-world case provided by an international infant formula company operating in Taiwan. The objective is minimising the total travel time. First, we present a four-phase heuristic to quickly generate a feasible schedule. We then apply a variable neighbourhood search incorporated with memory and revolver schemes to improve the solution quality. Through extensive computational experiments, it is shown that the proposed solution approaches are quite effective in terms of solution quality and computation time.