Lean beyond waste: Towards the reduction of variability and buffers in healthcare

Being Lean has become a popular approach towards process improvement in health care. The reduction of waste is considered central to a Lean approach. Next to the reduction of obvious waste, Lean initiatives are expected to reduce variability and consequential buffers. Variability can be classified as natural or artificial. The latter stems from one’s own actions and should be reduced. Where variability leads to buffering in general, time and capacity buffers are especially prevalent in health care. In addition to these well-established buffer types, this thesis also exposes the role of an unexplored buffering mechanism through adjustments of processing times.

Findings in this thesis contribute to the grounding of Lean theory, based on four research projects that investigated the roles of variability and buffers, mature Lean aspects, in a Lean context. Despite the large number of interventions investigated in the first project, only a few are shown to reduce variability and improve throughput time performance. Instead, the focus of interventions is skewed towards reducing specific types of obvious waste. Yet, knowledge on the roles of variability and buffers is shown to broaden the focus of interventions. This thesis shows several opportunities for improved lean applications in health care.